Filed Pursuant to Rule 424(b)(5)

Registration No. 333-218782

CALCULATION OF REGISTRATION FEE

PROSPECTUS SUPPLEMENT

(to prospectus dated June 16, 2017)

$30,000,000

5.00% Fixed-to-Floating Rate Subordinated Notes due December 31, 2027

We are offering $30,000,000.00 aggregate principal amount of our 5.00% fixed-to-floating rate subordinated notes due December 31, 2027, which we refer to herein as the “notes.” The notes will rank equally in right of payment with our other unsecured subordinated debt.

The notes will mature on December 31, 2027. From and including the date of issuance to but excluding December 31, 2022, the notes will initially bear interest at a fixed rate of 5.00% per year, payable semiannually on June 30 and December 31 of each year, beginning June 30, 2018. From and including December 31, 2022, to, but excluding, the maturity date, unless redeemed earlier, the notes will bear interest at a floating rate equal to three-month LIBOR (as defined herein) as calculated on each applicable determination date (as defined herein), plus a spread of 283 basis points, payable quarterly in arrears on March 31, June 30, September 30 and December 31 of each year, commencing on March 31, 2023. Notwithstanding the foregoing, if three-month LIBOR for the applicable floating rate interest period is less than zero, the three-month LIBOR rate will be deemed to be zero. The notes will not be listed on any securities exchange or included in any automated dealer quotation system.

Subject to the prior approval of the Board of Governors of the Federal Reserve System, or Federal Reserve Board, to the extent that such approval is required, we may, at our option, beginning December 31, 2022, and, on any scheduled interest payment date thereafter, redeem the notes, in whole or in part, at a redemption price equal to 100% of the principal amount of the notes to be redeemed plus accrued and unpaid interest to, but excluding, the date of redemption (an “Optional Redemption”). Other than in the case of an Optional Redemption, subject to the prior approval of the Federal Reserve Board, to the extent that such approval is required, the notes will not be redeemable prior to maturity unless certain events occur as described under “Description of Notes” in this prospectus supplement. There is no sinking fund for the notes. The notes will not be convertible or exchangeable.

The notes will be unsecured obligations of ours and will be subordinated in right of payment to all our existing and future senior indebtedness, whether secured or unsecured. Because Independent Bank Group, Inc. is a holding company, our cash flows, and, consequently, our ability to pay and discharge our obligations, including the principal of, and interest on, our debt securities, is dependent on dividends, distributions and other payments made to us by our subsidiaries, primarily our wholly-owned subsidiary, Independent Bank, which is a Texas state-chartered bank and funds we obtain from our corporate borrowings or sales of our securities. Our right to receive any payments or distribution of cash or assets from our subsidiaries upon their liquidation or reorganization, and the consequent right of the holders of our debt securities to participate in the proceeds of those payments or distributions, are effectively subordinated to the claims of our subsidiaries’ creditors and preferred equity holders, including depositors of Independent Bank. The notes are obligations of Independent Bank Group, Inc. only and are not obligations of, and are not guaranteed by, any of our subsidiaries, including our bank subsidiary, Independent Bank.

We are an “emerging growth company” as defined in the Jumpstart Our Business Startups Act, or the JOBS Act, and have been eligible for certain reduced public company reporting requirements as a result of such status. We will cease to being an “emerging growth company” on January 1, 2018. Please see “Summary—Emerging Growth Company Status” in this prospectus supplement.

Investing in the notes involves certain risks. Before investing in the notes, you should consider the information under the heading “Risk Factors” beginning on page S-12 of this prospectus supplement, and under the heading “Part I. Item 1A. Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2016 and under the heading “Part II. Item 1A. Risk Factors” in our Quarterly Report on Form 10-Q for the quarter ended September 30, 2017, which are incorporated herein by reference.

None of the Securities and Exchange Commission, the Federal Deposit Insurance Corporation, the Federal Reserve Board, nor any other regulatory body has approved or disapproved of the notes or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

The notes are not savings accounts, deposits or other obligations of any bank and are not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

The underwriters expect to deliver the notes in book-entry form only through the facilities of The Depository Trust Company and its participants against payment therefor in immediately available funds on or about December 19, 2017, which is the 3rd business day following the date of pricing of the notes (such settlement being referred to as “T+3”). See “Underwriting” for details.

Joint Book-Running Managers

Prospectus Supplement dated December 13, 2017

TABLE OF CONTENTS

Preliminary Prospectus Supplement

Prospectus

S-i

ABOUT THIS PROSPECTUS SUPPLEMENT AND THE ACCOMPANYING PROSPECTUS

This document is comprised of two parts. The first part is this prospectus supplement, which describes the specific terms of this note offering, the notes and certain other matters relating to us and our financial condition. This prospectus supplement also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The second part of this document is the accompanying prospectus, dated June 16, 2017, which is included as part of our automatic shelf registration statement on Form S-3 (File No. 333-218782). That registration statement and the accompanying prospectus provide more general information about securities that we and any selling securityholders may offer from time to time, some of which may not apply to this offering. You should read carefully both this prospectus supplement and the accompanying prospectus in their entirety, together with additional information described under the heading, “Where You Can Find More Information,” in this prospectus supplement before investing in the notes.

Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus supplement and the accompanying prospectus to “Independent Bank Group, Inc.,” “Independent,” the “Company,” “our Company,” “we,” “us,” “our” and “ours” or similar references mean Independent Bank Group, Inc. and its consolidated subsidiaries.

Neither the Company nor the underwriters have authorized anyone to provide you with any information other than that contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectus prepared by, or on behalf of the Company, or to which the Company has referred you. Neither the Company nor the underwriters take any responsibility for, or can provide any assurance as to the reliability of, any information that others may give you. If any information in this prospectus supplement is inconsistent with the accompanying prospectus, you should rely on the information in this prospectus supplement. You should not assume that the information provided in this prospectus supplement, the accompanying prospectus or the documents incorporated by reference in this prospectus supplement and in the accompanying prospectus is accurate as of any date other than the date of this prospectus supplement or the date of the document in which that information is contained. Our business, financial condition, liquidity, results of operations and prospects may have changed since the date of any document in which such information is contained.

Neither the Company nor the underwriters are offering to sell nor seeking an offer to buy the notes in any jurisdiction where such offers and sales are not permitted. The distribution of this prospectus supplement and the accompanying prospectus and the offering of the notes in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement and the accompanying prospectus must inform themselves about and observe any restrictions relating to the offering of the notes and the distribution of this prospectus supplement and the accompanying prospectus outside the United States. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used for or in connection with, an offer or solicitation by any person in any jurisdiction in which such offer or solicitation is not authorized or in which the person making such offer or solicitation is not authorized or is not qualified to do so or to any person to whom it is unlawful to make such offer or solicitation, and this prospectus supplement and the accompanying prospectus may not be delivered to any person to whom it is unlawful to make such offer or solicitation. See “Underwriting” in this prospectus supplement.

S-ii

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the United States Securities and Exchange Commission, or the SEC. You may read and copy any document that we file with the SEC at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. Our filings with the SEC are also available to the public through the SEC’s website at www.sec.gov.

Our annual, quarterly and current reports and any amendments to those reports are also available over the Internet at our website at www.ibtx.com. All internet addresses provided in this prospectus supplement or in the accompanying prospectus are for informational purposes only and are not intended to be hyperlinks. In addition, the information on, or accessible through, our website, or any other website described herein, is not a part of, and is not incorporated or deemed to be incorporated by reference in, this prospectus supplement or the accompanying prospectus or other offering materials.

We have filed an automatic shelf registration statement (File No. 333-218782) with the SEC registering the offering of various of our securities, including the notes offered by this prospectus supplement and the accompanying prospectus. This prospectus supplement and the accompanying prospectus are part of that registration statement. The registration statement may contain additional information that may be important to you. You may obtain from the SEC copies of the registration statement and the related exhibits that we filed with the SEC.

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC’s rules allow us to incorporate by reference information into this prospectus supplement and the accompanying prospectus. This means that we can disclose important information to you by referring you to another document. Any information incorporated by reference into this prospectus supplement and the accompanying prospectus is considered a part of the information contained herein and therein. We are incorporating by reference in this prospectus supplement, and have incorporated by reference in the accompanying prospectus, the documents listed below, which we have already filed with the SEC, and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or Exchange Act, except as to any portion of any future report or document that is deemed furnished to the SEC and not deemed filed under such provisions, so long as the registration statement of which the accompanying prospectus is a part remains effective:

The information contained in this prospectus supplement and the accompanying prospectus will be updated and supplemented by the information contained in the filings we make with the SEC in the future and that are incorporated by reference into this prospectus supplement and the accompanying prospectus as described above. The information contained in those future filings will be considered to be part of this prospectus supplement and

S-iii

the accompanying prospectus and will automatically update and supersede, as appropriate, the information contained in this prospectus supplement and the accompanying prospectus and contained in the filings previously filed with the SEC that are incorporated by reference into this prospectus.

Upon request, we will provide, without charge, to each person to whom a copy of this prospectus supplement and the accompanying prospectus is delivered a copy of the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. You may request a copy of these filings, and any exhibits we have specifically incorporated by reference as an exhibit to the registration statement to which the accompanying prospectus is a part, at no cost by writing or telephoning us at the following address:

Independent Bank Group, Inc.

1600 Redbud, Suite 400

McKinney, Texas 75069

Telephone: (972) 562-9004

Facsimile: (972) 562-5496

Attention: Investor Relations

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain statements contained in this prospectus supplement, the accompanying prospectus, and the documents incorporated by reference that are not statements of historical fact constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, that are subject to risks and uncertainties and are made pursuant to the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended, or Securities Act. These forward-looking statements include information about our possible or assumed future economic performance, future results of operations, including our future revenues, income, expenses, provision for loan losses, provision for taxes, effective tax rate, earnings per share and cash flows, and our future capital expenditures and dividends, future financial condition and changes therein, including changes in our loan portfolio and allowance for loan losses, future capital structure or changes therein, as well as the plans and objectives of management for our future operations, future or proposed acquisitions, the future or expected effect of acquisitions on our operations, results of operations, financial condition, and future economic performance and the statements of the assumptions underlying any such statement. Such statements are typically, but not exclusively, identified by the use in the statements of words or phrases such as “aim,” “anticipate,” “estimate,” “expect,” “goal,” “guidance,” “intend,” “is anticipated,” “is estimated,” “is expected,” “is intended,” “objective,” “plan,” “projected,” “projection,” “will affect,” “will be,” “will continue,” “will decrease,” “will grow,” “will impact,” “will increase,” “will incur,” “will reduce,” “will remain,” “will result,” “would be,” variations of such words or phrases (including where the word “could,” “may” or “would” is used rather than the word “will” in a phrase) and similar words and phrases indicating that the statement addresses some future result, occurrence, plan or objective. The forward-looking statements that we make are based on our current expectations and assumptions regarding our business, the economy, and other future conditions. Because forward-looking statements relate to future results and occurrences, they are subject to inherent uncertainties, risks, and changes in circumstances that are difficult to predict. Many possible events or factors could affect our future financial results and performance and could cause those results or performance to differ materially from those expressed in the forward-looking statements. These possible events or factors include, but are not limited to:

S-iv

S-v

We urge you to consider all of these risks, uncertainties and other factors as well as those risks discussed in this prospectus supplement, in the accompanying prospectus and in the documents incorporated herein by

S-vi

reference, including in our Annual Report on Form 10-K for the year ended December 31, 2016 and Form 10-Q for the quarter ended September 30, 2017, carefully in evaluating all such forward-looking statements made by us. As a result of these and other matters, including changes in facts, assumptions not being realized or other factors, the actual results relating to the subject matter of any forward-looking statement may differ materially from the anticipated results expressed or implied in any forward-looking statement. Any forward-looking statement made in this prospectus supplement, the accompanying prospectus or in any report, filing, document or information incorporated by reference in this prospectus supplement or the accompanying prospectus speaks only as of the date on which it is made. We undertake no obligation to update any such forward-looking statement, whether as a result of new information, future developments or otherwise, except as may be required by law.

A forward-looking statement may include a statement of the assumptions or bases underlying the forward-looking statement. We have chosen these assumptions or bases in good faith, and we believe that such assumptions and bases were reasonable at the date we published each related forward-looking statement. However, we caution you that assumptions as to future occurrences or results almost always vary from actual future occurrences or results, and the differences between assumptions and actual occurrences and results can be material. Therefore, we caution you not to place undue reliance on the forward-looking statements contained in this prospectus supplement, the accompanying prospectus or in any report, filing, document or information incorporated by reference herein or therein.

S-vii

S-1

S-2

S-3

S-4

S-5

S-6

S-7

S-8

S-9

S-10

S-11

RISK FACTORS

Investing in the notes involves a high degree of risk. Before making an investment decision, you should carefully consider the following risks, as well as those beginning in our Annual Report on Form 10-K for the year ended December 31, 2016, and our Quarterly Report on Form 10-Q for the quarter ended September 30, 2017, and all of the other information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus. The realization of any of the matters referenced as risk factors could have a material adverse effect on our business, financial condition, liquidity, results of operation and prospects, and holders of the notes could lose some or all of their investment.

Risks Related to the Notes and This Offering

The notes are subordinated to our senior indebtedness and to the obligations of our subsidiaries.

The notes are our subordinated, unsecured obligations and, consequently, are junior in right of payment to all of our secured and unsecured senior indebtedness now existing or that we incur in the future. As a result, if we become subject to any termination, winding up, liquidation or reorganization, including as a result of any liquidation, reorganization or other insolvency proceeding under bankruptcy laws or any other applicable insolvency law, make any assignment for the benefit of our creditors or otherwise engage in any marshalling of our assets and liabilities, the holders of the senior indebtedness would be entitled to have the senior indebtedness paid in full prior to the holders of the notes receiving any payment of principal of, or interest on, the notes. In addition, if a default in the payment of principal of, or interest on, any senior indebtedness occurs and is continuing past any applicable grace period or if any event of default occurs and is continuing with respect to any senior indebtedness or would occur with respect to any senior indebtedness if we pay the principal of, or any interest on, the notes and that event of default would allow the holders of such senior indebtedness to accelerate the maturity of such senior indebtedness, we may not pay the principal of, or any interest on, the notes until such default or event of default with respect to the senior indebtedness is cured or waived or otherwise ceases to exist. The senior indebtedness to which the notes are subordinated is described below under “Description of the Notes—Subordination of the Notes.”

As of September 30, 2017, and the date of this prospectus supplement, we did not have any senior indebtedness outstanding, although we have in effect a senior revolving credit facility under which we may borrow up to a total of $50.0 million to be outstanding at any one time that was undrawn at each such date. That revolving credit facility expires by its terms on October 19, 2018, unless the term of such facility is extended. The subordinated debt indenture, which governs the notes, does not limit the amount of additional indebtedness or senior indebtedness that we may incur or the amount of indebtedness that Independent Bank may incur. In the future, we may issue senior or subordinated debt securities, including additional notes of the series of our debt securities of which the notes offered hereby are a part, and incur other indebtedness, which may be substantial in amount, including secured indebtedness, indebtedness that is senior in right of payment to the notes and indebtedness ranking equally in right of payment with the notes. In addition, Independent Bank could incur indebtedness of which it is the obligor, and that indebtedness would be structurally senior to the notes.

As a consequence of the subordination of the notes to our senior indebtedness, an investor in the notes might lose all or some of its investment should we liquidate or become insolvent. In such an event, our assets would be available to pay the principal of and accrued and unpaid interest on the notes only after all of our senior indebtedness has been paid in full. Moreover, we could issue other subordinated debt securities that would rank equally in right of payment to the notes. In the event of our liquidation or any liquidation, reorganization or other insolvency proceedings under the U.S. Bankruptcy Code or any other insolvency law, the notes, together with such other subordinated debt securities and any of our other general, unsecured obligations that do not constitute senior indebtedness will share pro rata in our assets remaining for payment of such obligations after we have paid all of our senior indebtedness in full.

S-12

The notes will be structurally subordinate to the obligations of Independent Bank and our other subsidiaries, and the holders of those obligations will be entitled to receive payment in full of those obligations before we participate in any distribution of the assets of Independent Bank and our other subsidiaries in the event of their liquidation or insolvency.

The notes are obligations exclusively of Independent Bank Group and are not obligations of Independent Bank. Independent Bank is a separate and distinct legal entity from Independent Bank Group, will not be an obligor with respect to the notes, will not guarantee the payment of the notes and will have no obligation to pay any amounts to Independent Bank Group, including any dividends, to make any other distributions to Independent Bank Group or to provide Independent Bank Group with funds to meet or discharge any of Independent Bank Group’s obligations or liabilities, including the notes. Independent Bank Group’s rights and the rights of its creditors, including the holders of the notes, to participate in any distribution of the assets of Independent Bank (either as a shareholder or as a creditor), upon a liquidation, reorganization, insolvency or receivership of Independent Bank (and the consequent right of the holders of the notes to participate in those assets after repayment of our senior indebtedness), will be subject to the claims of the creditors of Independent Bank, including depositors in Independent Bank. As a consequence of the foregoing, the notes will be effectively structurally subordinate to all of the obligations and liabilities of Independent Bank and Independent Bank Group’s other subsidiaries to the extent that the liabilities of Independent Bank, including its deposit liabilities, and our other subsidiaries equal or exceed the realizable value of their respective assets.

Regulatory guidelines may restrict our ability to pay the principal of, and accrued and unpaid interest on, the notes, regardless of whether we are the subject of an insolvency proceeding.

As a bank holding company, our ability to pay the principal of, and interest on, the notes is subject to the guidelines of the Federal Reserve Board regarding capital adequacy. We intend to treat the notes as “Tier 2 capital” of our Company under the Federal Reserve Board’s regulatory capital rules and guidelines. The Federal Reserve Board guidelines generally require us to review the effects of the cash payment of Tier 2 capital instruments such as the notes on our overall financial condition. The guidelines also require that we review our net income for the current and past four quarters, and the amounts we have paid on Tier 2 capital instruments for those periods, as well as our projected rate of earnings retention. Moreover, under Federal Reserve Board policy, a bank holding company is required to act as a source of financial and managerial strength to each of its banking subsidiaries and commit resources to their support, including the guarantee of capital plans of an undercapitalized bank subsidiary. Such support may be required at times when a holding company may not otherwise be inclined to provide it. We may be unable to pay accrued interest on the notes on one or more of the scheduled interest payment dates or at any other time or the principal of the notes at the maturity of the notes.

If Independent Bank Group were to be the subject of a bankruptcy proceeding under Chapter 11 of the U.S. Bankruptcy Code, the bankruptcy trustee would be deemed to have assumed and would be required to cure immediately any deficit under any commitment we have to any of the federal banking agencies to maintain the capital of Independent Bank and any other insured depository institution for which we have such a responsibility, and any claim for breach of such obligation would generally have priority over most other unsecured claims.

We depend primarily on cash dividends from our subsidiary, Independent Bank, to meet our cash obligations. Failure of Independent Bank to pay sufficient cash dividends to us would prevent us from paying interest on the notes or the principal of the notes at maturity.

Independent Bank Group is a holding company and reports financial information on a consolidated basis with its subsidiaries. Substantially all of the assets of the consolidated companies are owned by our subsidiaries, in particular, Independent Bank. Dividends from Independent Bank provide a substantial portion of Independent Bank Group’s cash flow and are the source of the funds that we will use to pay interest on the notes. Various regulatory provisions limit the amount of dividends Independent Bank can pay to Independent Bank Group without regulatory approval. In certain cases, regulatory authorities may even prohibit Independent Bank from

S-13

paying dividends to Independent Bank Group. Moreover, the terms of the notes do not provide for us to make payments into any sinking fund with respect to the notes out of which the principal of, or accrued and unpaid interest on, the notes could be paid. If Independent Bank cannot pay dividends to us for any period as a result of any regulatory limitation or prohibition or cannot, for any other reason, pay dividends in an amount sufficient for us to pay the principal of, or accrued and unpaid interest on, the notes, we would be unable to pay the interest on or principal of the notes unless we are able to borrow funds from other sources or sell additional securities of Independent Bank Group to obtain funds necessary to make one or more such payments of accrued and unpaid interest on, and to pay the principal of, the notes. Independent Bank paid Independent Bank Group approximately $36.0 million and approximately $25.5 million in dividends during the year ended December 31, 2016, and the nine months ended September 30, 2017, respectively. We paid interest of $5.8 million and $7.2 million on our outstanding indebtedness in the year ended December 31, 2016, and the nine months ended September 30, 2017, respectively.

There is no established trading market for the notes, which could make it more difficult for you to sell your notes and could adversely affect the price of the notes in any trading market that develops in the notes following the offering.

The notes constitute a new issue of securities for which no established trading market exists. Consequently, it may be difficult for you to sell your notes. We do not intend to list the notes on any securities exchange or to apply to have the notes quoted on any automated dealer quotation system. A market for the notes may not develop, and if such a market does develop, such market may not continue to exist or provide liquidity for the notes following the offering or provide a market at prices for the notes acceptable to investors.

The amount of interest payable on the notes will vary from interest period to interest period after December 31, 2022.

Because three-month LIBOR is a floating rate, the interest rate on the notes will vary from interest period to interest period after December 31, 2022, at a floating rate equal to three-month LIBOR, as calculated on each applicable determination date, provided that if the three-month LIBOR rate is less than zero, then the three-month LIBOR rate shall be deemed to be zero, plus 283 basis points (2.83%) per year. The interest rate that is determined on the relevant determination date will apply to the entire interest period following such determination date, even if three-month LIBOR increases during that period.

Changes in inter-bank lending rate reporting practices or the method pursuant to which LIBOR rates are determined may adversely affect the value of the notes.

Beginning in 2008, concerns have been raised that some of the member banks surveyed by the British Bankers’ Association, or the BBA, in connection with the calculation of daily LIBOR rates, which rates were referred to as “BBA LIBOR,” may have been under-reporting the inter-bank lending rate applicable to them in order to avoid an appearance of capital insufficiency or adverse reputational or other consequences that could result from reporting higher interbank lending rates or to increase the value of trading positions. On December 19, 2012, US, UK and Swiss governmental authorities announced a $1.5 billion settlement with UBS AG for its involvement in misreporting BBA LIBOR and other rates. In connection with this settlement, UBS’s Japanese subsidiary pleaded guilty to fraud and the US Department of Justice charged two former UBS traders with criminal conspiracy. In June 2012, Barclays Bank was fined $451 million by governmental authorities in the United States and the United Kingdom, or the UK, for that bank’s involvement in misreporting BBA LIBOR. Inquiries remain ongoing, including investigations by regulators and governmental authorities in various jurisdictions. Such under-reporting may have resulted in the BBA LIBOR rate being artificially low. If any such under-reporting still exists and some or all of the member banks discontinue such practice, there may be a resulting sudden or prolonged upward movement in BBA LIBOR rates.

In addition, the final report of the Wheatley Review of BBA LIBOR, published in September 2012, set forth recommendations relating to the setting and administration of BBA LIBOR, and in March 2013, the UK’s

S-14

Financial Services Authority, or the FSA, finalized new rules that bring regulatory oversight of LIBOR under the scope of the UK government. Effective April 1, 2013, the FSA was replaced by the UK’s Financial Conduct Authority, or the FCA, and the UK’s Prudential Regulation Authority, with the Bank of England having overall responsibility for financial stability and BBA LIBOR benchmarks falling under the scope of the FCA. Among the new rules, administrators and banks must appoint an individual, approved by the FCA, to oversee compliance and banks will be required to have in place clear conflicts of interest policies and appropriate systems and controls. At the present time, it is uncertain what further changes, if any, may be made by the UK government or other governmental or regulatory authorities in the method for determining BBA LIBOR, whether any such further changes would cause any decrease or increase in LIBOR rates or whether BBA LIBOR will continue to be reported or quoted by banks for deposits in U.S. dollars in the London interbank market. Proposed changes include a reduction in the number of currencies and tenors for which LIBOR is calculated, and changes in how LIBOR is calculated by basing submissions on actual transactions data.

Furthermore, on July 27, 2017, the FCA announced that it will no longer persuade or compel banks to submit LIBOR rates after 2021 (the “FCA Announcement”). It is not possible to predict the effect of the FCA Announcement, any changes in the methods pursuant to which the LIBOR rates are determined and any other reforms to LIBOR that will be enacted in the U.K. and elsewhere, which may adversely affect the trading market for LIBOR-based securities, including the notes, or result in the phasing out of LIBOR as a reference rate for securities. In addition, any changes announced by the FCA, including the FCA Announcement, the ICE Benchmark Administration Limited or any other successor governance or oversight body, or future changes adopted by any such body in the method pursuant to which the LIBOR rates are determined may result in a sudden or prolonged increase or decrease in the reported LIBOR rates.

Any changes in the method pursuant to which LIBOR rates are determined, or the development of a widespread market view that LIBOR rates are being manipulated by IBA or any other market participants involved in any manner in the determination of LIBOR rates, may result in a sudden or prolonged increase or decrease in the reported LIBOR rates. If any such change or development were to occur, the level of interest payments and the value of the notes may be adversely affected.

In addition, if the three-month LIBOR is not available on any determination date for any reason, then the rate for the applicable Floating Rate Interest Period (as defined below) will be determined using the alternative methods described in “Description of the Notes—Payment of Principal and Interest – Floating Rate Period.” Any of these alternative methods may result in interest payments that are lower than, or that do not otherwise correlate over time with, the interest payments that would have been made on the notes if three-month LIBOR were available in its current form. The final alternative method sets the interest rate for the applicable Floating Rate Interest Period to equal the three-month LIBOR for the then current Floating Rate Interest Period or, in the case of the first Floating Rate Interest Period, 2.17% (resulting in a 5.00% interest rate on the notes for such Floating Rate Interest Period).

The use of any alternative method to calculate a floating rate of interest with respect to the notes, or other consequential changes to LIBOR as a result of international, national, or other proposals for reform or other initiatives or investigations, or any further uncertainty in relation to the timing and manner of implementation of such changes, could have a material adverse effect on the value of and return on the notes. The indenture requires the Company to appoint a calculation agent to calculate the interest rate for each interest rate period during the floating rate period. If the Company does not engage such a third party to act as the calculation agent on or before the determination date for the first Floating Rate Interest Period, the Company will serve as the calculation agent and will be responsible for calculating the interest rate for each floating rate interest period while serving as the calculation agent.

You will have no rights against the publishers of LIBOR.

You will have no rights against any person publishing LIBOR rates, even though the amount you receive on each interest payment date after December 31, 2022 will depend on the level of the three-month LIBOR rate

S-15

quoted for each interest period during the period for which the notes bearing interest at a floating rate. The publishers of LIBOR are not in any way involved in this offering and have no obligations relating to the notes or the holders of the notes.

Because the notes may be redeemed at our option at any time after December 31, 2022 and, under certain circumstances, prior to their maturity, you may be subject to reinvestment risk.

We will have the right, subject to the receipt of any required approval of the Federal Reserve Board, to redeem the notes at our option (i) in whole or in part on any interest payment date on or after December 31, 2022 and (ii) in whole, but not in part, at any time within 90 days following certain events as described under “Description of the Notes—Optional Redemption and Redemption Upon Special Events,” in each case at a redemption price equal to 100% of the principal amount of the notes, plus unpaid interest, if any, accrued thereon to but excluding the date of redemption. If the interest payable on the notes on or after December 31, 2022 is higher than the yield payable in respect of a comparable issuer and security, it is more likely that we would exercise our right to redeem the notes prior to their stated maturity. Any such redemption may have an adverse effect on the income and return otherwise receivable on an investment in the notes by reducing the term of such investment. If an early redemption occurs, you may not be able to reinvest the proceeds from such redemption in a comparable issuer and security at the same or higher yield relative to our notes.

The notes contain limited events of default, and the remedies available thereunder are limited.

As described in “Description of the Notes — Events of Default; Limitation on Suits,” the notes contain limited events of default and remedies. As a result of our intent to treat all of the notes as Tier 2 capital after the consummation of the offering of the notes, the ability of the trustee under the subordinated debt indenture that governs the notes and the holders of the notes to accelerate the maturity of and our obligation to pay immediately the principal of, and any accrued and unpaid interest on the notes will be limited to the events of default that occur upon the entry of a decree or order for relief in respect of Independent Bank Group by a court having jurisdiction in the premises in an involuntary proceeding under Chapter 7 (liquidation) or Chapter 11 (reorganization) of the U.S. Bankruptcy Code as now or hereafter in effect, and such decree or order having continued unstayed and in effect for a period of 60 consecutive days or if Independent Bank Group commences a bankruptcy or insolvency proceeding or consents to the entry of an order in an involuntary proceeding under Chapter 7 (liquidation) or Chapter 11 (reorganization) of the U.S. Bankruptcy Code as now or hereafter in effect. Consequently, neither the trustee nor any holder of notes has or will have the right to accelerate the maturity of the notes in the case of our failure to pay the principal of, or interest on, the notes or our nonperformance of any other covenant or warranty under the notes or the indenture. The holders of our outstanding subordinated notes and junior subordinated debentures are subject to substantially the same limitations, but the holders of our senior indebtedness are not and will not be subject to limitations of that type. If the holders of our senior indebtedness are able to accelerate the maturity of some or all of our senior indebtedness at a time when a noninsolvency default has occurred, but an insolvency default has not occurred, with respect to the notes, such holders of our senior indebtedness may be able to accelerate the maturity of, and pursue the payment in full of, that senior indebtedness while the holders of the notes would be unable to pursue similar remedies with respect to the notes.

No limit or restriction exists on the amount or type of further securities or indebtedness that we may issue, incur or guarantee, and the indenture governing the notes does not contain any financial covenants.

No limit or restriction exists on the amount of securities or other liabilities that we may issue, incur or guarantee and that rank senior in right of payment to, or pari passu with, the notes. The issuance or guarantee of any such securities or the incurrence of any such other liabilities may reduce the amount, if any, recoverable by holders of the notes in any reorganization under the Bankruptcy Code or any liquidation or winding up under the Bankruptcy Code or otherwise of Independent Bank Group and may limit Independent Bank Group’s ability to meet its obligations under the notes. In addition, neither the indenture nor the notes contain any restriction on Independent Bank Group’s ability to issue securities that may have preferential rights to the notes or securities

S-16

with provisions similar to or different from the provisions of the indenture under which the notes are issued. Neither such indenture nor the notes contain any financial covenants that would require us to achieve or maintain any minimum financial results relating to our financial position or results of operations or meet or exceed certain financial ratios, as a general matter or in order to incur additional indebtedness or obligations, or to maintain any reserves. Moreover, neither such indenture nor the notes contain any covenants prohibiting us from, or limiting our right to, incur additional indebtedness or obligations, to grant liens on our assets to secure our indebtedness or other obligations, to repurchase our stock or other securities, including any of the notes or any of our other outstanding debt securities, or to pay dividends or make other distributions to our shareholders. In addition, neither the indenture nor the notes contain any provision that would provide protection to the holders of the notes against a sudden and dramatic decline in our credit quality resulting from a merger, takeover, recapitalization or similar restructuring or any other event involving us or our subsidiaries that may adversely affect our credit quality.

The market value of the notes may be influenced by unpredictable factors.

Certain factors, many of which beyond our control, will influence the value of the notes and the price, if any, at which securities dealers and others may be willing to purchase or sell the notes in any secondary market for the notes, including:

Accordingly, if an investor in the notes sells those notes in the secondary market, it may not be able to obtain a price that will provide it with a desired yield, a price equal to the principal amount of the notes or a price equal to the price that the investor paid for the notes.

The notes are not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

The notes are not savings accounts, deposits or other obligations of any bank and are not insured or guaranteed by the Federal Deposit Insurance Corporation, or FDIC, or any other governmental agency or instrumentality.

Our management will have broad discretion as to the use of the net proceeds to us from this offering, and we may not use the proceeds effectively.

We intend to use the net proceeds from this offering, after the payment of offering expenses, for general corporate purposes, including to increase our consolidated capital to support continued growth through acquisitions and continued organic growth. We may apply the net proceeds from the offering in one or more ways with which some investors in this offering may not agree. Moreover, our management may use such net proceeds in ways that do not improve our financial position or results of operations or enhance the value of our common stock. You will not have the opportunity, as part of your investment decision, to assess whether these proceeds are being used appropriately. Management’s failure to use such funds effectively could have an adverse effect on our business, results of operations and financial condition. See “Use of Proceeds.”

S-17

Risks Related to the Pending Acquisition of Integrity Bancshares

The pending acquisition of Integrity Bancshares may not be completed.

Completion of the acquisition of Integrity Bancshares with and into Independent Bank is subject to regulatory approval. We cannot assure you that we will be successful in obtaining required regulatory approvals. If we are not successful in obtaining required regulatory approvals, the acquisition will not be completed. If such regulatory approvals are received, there can be no assurance as to the timing of those approvals or whether any conditions will be imposed that would result in certain closing conditions of the acquisition not being satisfied.

The consummation of the acquisition is also subject to other conditions precedent described in the reorganization agreement between the Company and Integrity Bancshares. If a condition of either party is not satisfied, that party may be able to terminate the reorganization agreement and, in such case, the acquisition would not be consummated. We cannot assure you that all of the conditions precedent in the reorganization agreement will be satisfied or that the acquisition of Integrity Bancshares will be completed.

Integrity Bancshares and Integrity Bank will be subject to business uncertainties and contractual restrictions while the acquisition is pending.

Uncertainty about the effect of the acquisition on employees and customers may have an adverse effect on Integrity Bancshares and Integrity Bank and, consequently, on Independent and Independent Bank. Uncertainties surrounding the acquisition may impair the ability of one or more of the Company, Independent Bank, Integrity Bancshares and Integrity Bank to attract, retain and motivate key personnel until the acquisition is completed, and could cause customers and others that deal with either of the banks to seek to change their existing business relationships with such bank. In addition, the reorganization agreement restricts Integrity Bancshares and Integrity Bank from taking other specified actions until the acquisition occurs without Independent’s consent. These restrictions may prevent Integrity Bancshares or Integrity Bank from pursuing attractive business opportunities that may arise prior to the completion of the acquisition.

Integrating Integrity Bank into Independent Bank’s operations may be more difficult, costly or time-consuming than Independent expects.

Independent Bank and Integrity Bank will continue to operate independently until the acquisition is completed. Accordingly, the process of integrating Integrity Bank’s operations into Independent Bank’s operations could result in the disruption of operations or the loss of Integrity Bank customers and employees and make it more difficult to achieve the intended benefits of the acquisition. Inconsistencies between the standards, controls, procedures and policies of Independent Bank and those of Integrity Bank could adversely affect Independent Bank’s ability to maintain relationships with current customers and employees of Integrity Bank if and when the acquisition is completed.

As with any acquisition of banking institutions, business disruptions may occur that may cause Independent Bank to lose customers or may cause Integrity Bank’s customers to withdraw their deposits from Integrity Bank prior to the acquisition’s consummation and from Independent Bank thereafter. The realization of the anticipated benefits of the acquisition may depend in large part on Independent’s ability to integrate Integrity Bank’s operations into Independent Bank’s operations, and to address differences in business models and cultures. If Independent is unable to integrate the operations of Integrity Bancshares and Integrity Bank into Independent’s and Independent Bank’s operations successfully and on a timely basis, some or all of the expected benefits of the acquisition may not be realized. Difficulties encountered with respect to such matters could result in an adverse effect on the financial condition, results of operations, capital, liquidity or cash flows of Independent Bank and the Company.

S-18

The Company may fail to realize the cost savings anticipated from the acquisition.

Although the Company anticipates that it would realize certain cost savings as to the operations of Integrity Bancshares and Integrity Bank and otherwise from the acquisition if and when the operations of Integrity Bancshares and Integrity Bank are fully integrated into the Company’s and Independent Bank’s operations, it is possible that the Company may not realize all of the cost savings that the Company has estimated it can realize from the acquisition. For example, for a variety of reasons, the Company may be required to continue to operate or maintain some facilities or support functions that are currently expected to be combined or reduced as a result of the acquisition. The Company’s realization of the estimated cost savings also will depend on the Company’s ability to combine the operations of the Company and Independent Bank with the operations of Integrity Bancshares and Integrity Bank in a manner that permits those costs savings to be realized. If the Company is not able to integrate the operations of Integrity Bancshares and Integrity Bank into the Company’s and Independent Bank’s operations successfully and to reduce the combined costs of conducting the integration operations of the two banks, the anticipated cost savings may not be fully realized, if at all, or may take longer to realize than expected. The Company’s failure to realize those cost savings could materially adversely affect Independent’s financial condition, results of operations, capital, liquidity or cash flows.

S-19

USE OF PROCEEDS

We expect to that the net proceeds from this offering to us, after the underwriting discount and estimated offering expenses payable by us, will be approximately $29.3 million.

We intend to use the net proceeds from this offering, after the payment of offering expenses, for general corporate purposes, including to increase our consolidated capital to support continued growth through acquisitions and continued organic growth.

Our management will have broad discretion in the application of the net proceeds from this offering, and investors will be relying on the judgment of our management with regard to the use of these net proceeds. Pending the use of the net proceeds from this offering as described above, we may invest the net proceeds in short-term, investment-grade, interest-bearing instruments.

S-20

CAPITALIZATION

You should read this information together with our consolidated historical financial statements and the related notes thereto incorporated by reference into this prospectus supplement and the accompanying prospectus.

The following table sets forth our cash and cash equivalents and capitalization, including regulatory capital ratios, on a consolidated basis, as of September 30, 2017, on an actual basis as of that date and as adjusted to give effect to (i) our sale of 448,500 shares of our common stock, in an SEC-registered public offering that was consummated on December 6, 2017, (ii) this offering and (iii) as adjusted to give effect to such equity offering and this offering, in the case of this offering, taking into account the expected net proceeds of such offering to us (after deducting the respective underwriting discounts and estimated offering expenses payable by us):

S-21

RATIOS OF EARNINGS TO FIXED CHARGES

Our historical ratios of earnings to fixed charges for the periods indicated are set forth in the table below. The ratio of earnings to fixed charges is computed by dividing (1) income from continuing operations before income taxes and fixed charges, both excluding and including interest on deposits, by (2) total fixed charges, both excluding and including interest on deposits. For purposes of computing these ratios:

S-22

DESCRIPTION OF THE NOTES

We will issue the notes under the subordinated debt indenture, dated as of June 25, 2014, between Independent Bank Group, Inc., as the issuer, and Wells Fargo Bank, National Association, as the trustee, as amended and supplemented by a first supplemental indenture dated as of July 17, 2014 (which established our series of 5.875% subordinated notes due August 1, 2024) and a second supplemental indenture (which will establish our series of 5.00% fixed-to-floating rate subordinated notes due December 31, 2027). We refer to this subordinated debt indenture, as amended and supplemented by the first supplemental indenture and as it is to be amended and supplemented by the second supplemental indenture, as the indenture, and we refer to Wells Fargo Bank, National Association, or Wells Fargo, in its capacity as the trustee under the indenture, as the trustee. The notes will be issued under and governed by the indenture. You may request a copy of the indenture from us as described under “Where You Can Find More Information” in the accompanying prospectus. The following summary of certain provisions of the notes in this prospectus supplement and the summary of certain provisions of our debt securities and the indenture in the accompanying prospectus do not purport to be complete and are subject to and qualified in their entirety by reference to all of the provisions of the notes and the indenture, including the definitions of certain terms used in the notes and the indenture. We urge you to read these documents because they, and not this description, define your rights as a holder of the notes.

General

The notes will be unsecured, subordinated obligations of our Company and will mature on December 31, 2027 unless redeemed prior to such date in accordance with the provisions set forth below under “—Optional Redemption and Redemption Upon Special Events.” The notes will be issued and may be transferred only in denominations of $1,000 or any amount in excess thereof that is an integral multiple of $1,000. Unless previously purchased and cancelled or redeemed prior to maturity, we will repay the notes at 100% of their principal amount, together with accrued and unpaid interest thereon, at their maturity. We will pay principal of and interest on the notes in U.S. dollars. The notes will constitute our unsecured debt obligations and will rank equally among themselves and with our existing subordinated notes due 2024 and will rank junior in right of payment to our senior indebtedness as described below in “—Subordination of the Notes.” No sinking fund will exist for the notes, and no sinking fund payments will be made with respect to the notes. The notes will not be convertible into or exchangeable for any other securities or property. The notes will not be subject to defeasance or covenant defeasance. Except as described below under “—Clearance and Settlement,” the notes will be issued only in book-entry form and will be represented by a global note registered in the name of Cede & Co, as the nominee of DTC. See “—Clearance and Settlement” below.

The notes are a part of a series of our subordinated debt securities that will be established under the subordinated debt indenture upon the execution by us and the trustee of the second supplemental indenture. We may, from time to time, without notice to, or the consent of, the holders of the notes, issue additional notes ranking equally with the notes and/or with identical terms to the notes in all respects (except for the issue date, the price of issuance, the payment of interest accruing prior to the issue date of such additional notes and the first payment of interest following the issue date of such additional notes) in order that such additional notes may be consolidated and form a single series with the notes and have the same terms as to status, redemption or otherwise as the notes. However, any additional notes of the series of which the notes are a part that are issued and are not fungible with the outstanding notes of such series for U.S. federal income tax purposes will be issued under one or more separate CUSIP and ISIN numbers. No limit exists on the aggregate principal amount of the notes of this series that we may issue.

The indenture contains no covenants or restrictions restricting the incurrence of indebtedness or other obligations by us or by our subsidiaries, including Independent Bank. The indenture contains no financial covenants requiring us to achieve or maintain any minimum financial results relating to our financial position or results of operations or meet or exceed any financial ratios, as a general matter or in order to incur additional

S-23

indebtedness or obligations, or to maintain any reserves. Moreover, neither the indenture nor the notes contain any covenants prohibiting us from, or limiting our right to, incur additional indebtedness or obligations, to grant liens on our assets to secure our indebtedness or other obligations that are senior in right of payment to the notes, to repurchase our stock or other securities, including any of the notes, or to pay dividends or make other distributions to our shareholders. In addition, neither the indenture nor the notes contain any provision that would provide protection to the holders of the notes against a sudden and dramatic decline in our credit quality resulting from a merger, takeover, recapitalization or similar restructuring or any other event involving us or our subsidiaries that may adversely affect our credit quality.

The notes and the indenture are governed by, and shall be construed in accordance with, the laws of the State of Texas.

The notes are not deposits in Independent Bank and are not insured or guaranteed by the FDIC or any other government agency or instrumentality. The notes are solely obligations of the Company and are neither obligations of, nor guaranteed by, Independent Bank or any of our other subsidiaries or affiliates.

No recourse will be available for the payment of principal of or interest on any note, for any claim based thereon, or otherwise in respect thereof, against any incorporator, shareholder, employee, agent, officer or director, as such, past, present or future, of ours or of any successor entity.

Payment of Principal and Interest

Payment of the full principal amount of the notes will be due on December 31, 2027, or the maturity date, unless the notes are purchased and cancelled or redeemed prior to the maturity date.

Fixed Rate Period

Unless redeemed prior to the maturity date as contemplated below under “—Optional Redemption and Redemption Upon Special Events,” from and including the date of issuance to, but excluding, December 31, 2022, which we refer to as the “Fixed Rate Period,” the notes will bear interest at an initial rate of 5.00% per year. During the Fixed Rate Period, interest on the notes will accrue from and including December 19, 2017, and will be payable semiannually in arrears on each June 30 and December 31 during the Fixed Rate Period, each a “Fixed Period Interest Payment Date,” commencing on June 30, 2018. During the Fixed Rate Period, interest will be computed on the basis of a 360-day year consisting of twelve 30-day months. The interest payable on the notes on any Fixed Period Interest Payment Date will, except as noted below, be paid to the person in whose name the notes are registered at the close of business on June 15 or December 15 (whether or not a business day) immediately preceding the Fixed Period Interest Payment Date. If any Fixed Period Interest Payment Date for the notes or the date for the payment of principal for the notes occurring during the Fixed Rate Period falls on a day that is not a business day (as defined below), the Company will postpone the interest or principal payment to the next succeeding business day, but the payments made on such dates will be treated as being made on the date that the payment was first due and the holders of the notes will not be entitled to any further interest, principal or other payments with respect to such postponements.

Floating Rate Period

Unless redeemed prior to such date as contemplated below under “—Optional Redemption and Redemption Upon Special Events,” from and including December 31, 2022, to, but excluding, the maturity date, which we refer to as the “Floating Rate Period,” the notes will bear interest at a floating rate equal to the three-month LIBOR, reset quarterly, as calculated on each determination date provided that if the three-month LIBOR rate is less than zero, then the three-month LIBOR rate shall be deemed to be zero, plus a spread of 283 basis points. A “Floating Rate Interest Period” means the period from and including each Floating Period Interest Payment Date

S-24

(as defined below) to, but excluding, the next succeeding Floating Period Interest Payment Date, except the initial Floating Rate Interest Period will be the period from and including December 31, 2022 to, but excluding, the next succeeding Floating Period Interest Payment Date.

During the Floating Rate Period, interest on the notes will accrue from and including December 31, 2022 and will be payable quarterly in arrears on March 31, June 30, September 30 and December 31 of each year, each a “Floating Period Interest Payment Date” and, together with any Fixed Period Interest Payment Date, an “Interest Payment Date,” commencing on March 31, 2023 and interest will be computed on the basis of the actual number of days in a Floating Rate Interest Period and a 360-day year. All percentages used in or resulting from any calculation of three-month LIBOR will be rounded, if necessary, to the nearest one hundred-thousandth of a percentage point, with 0.000005% rounded up to 0.00001%. The Company shall notify the trustee in writing of the interest rate for each Floating Rate Period on the applicable determination date.

If any Floating Period Interest Payment Date or the maturity date for the notes falls on a day that is not a business day, the Company will postpone the interest payment or the payment of principal and interest at maturity to the next succeeding business day (and, with respect to the maturity date, no additional interest will accrue on the amount payable for the period from and after the maturity date) unless, with respect to a Floating Period Interest Payment Date only, such day falls in the next calendar month, in which case the Floating Period Interest Payment Date will instead be the immediately preceding day that is a business day, and interest will accrue to, but excluding, such Floating Period Interest Payment Date as so adjusted.

The term “business day” with respect to the notes means any calendar day that is not a Saturday, Sunday or that is not a day on which banking institutions are authorized or obligated by law, regulation or executive order to be closed in The City of New York, New York, and on which the trustee and commercial banks are open for business in New York, New York; provided, however, that in the case of any Floating Period Interest Payment Date, such day is also a London Banking Day (as defined below); provided, further, that such term shall mean, when used with respect to any payment of principal of, or premium, if any, or interest on the notes to be made at any Place of Payment (as defined below) for the notes any day other than a Saturday, Sunday or other day on which banking institutions in such Place of Payment are authorized or obligated by law, regulation or executive order to close.

The term “London Banking Day” means any date on which commercial banks are open for business (including dealings in U.S. dollars) in London.

The interest payable on the notes on any Floating Period Interest Payment Date, subject to certain exceptions, will be paid to the person in whose name the notes are registered on the books of the Company or the Security Registrar at the close of business on March 15, June 15, September 15 or December 15 (whether or not a business day) immediately preceding the applicable Floating Period Interest Payment Date. Payments will include interest accrued to, but excluding, the relevant Floating Period Interest Payment Date. However, interest that the Company pays on the maturity date will be paid to the person to whom the principal will be payable. Interest will be payable by wire transfer in immediately available funds in U.S. dollars at the office of the principal paying agent in New York, New York or, at the Company’s option in the event the notes are not represented by global notes, by check mailed to the address of the person specified for payment in the preceding sentences.

The term “three-month LIBOR” means, as determined by the Calculation Agent (as defined below) on the second London Banking Day immediately preceding the commencement of the applicable Floating Rate Interest Period (the “determination date”) and provided to the trustee in writing, the offered rate for deposits in U.S. dollars having a maturity of three months that appears on the Designated LIBOR Page as of approximately 11:00 a.m., London time, on such determination date. If such rate does not appear on the Designated LIBOR Page at such time, or the Designated LIBOR Page is not available on such date, the Calculation Agent shall obtain such rate from Bloomberg L.P.’s page “BBAM” (or any successor or replacement page). If the Calculation Agent

S-25

determines that such rate has been discontinued, then it shall determine in its sole discretion whether to use a substitute or successor base rate that is most comparable to such rate, provided that if the Calculation Agent determines there is an industry accepted successor base rate, the Calculation Agent shall use such successor base rate, and if the Calculation Agent has determined a substitute or successor base rate in accordance with the foregoing, the Calculation Agent in its sole discretion may also implement changes to the business day convention, any business day definition, the determination date and any method for obtaining the substitute or successor base rate if such rate is unavailable on the relevant business day, in a manner that is consistent with industry accepted practices for such substitute or successor base rate. If the Calculation Agent determines that such rate has been discontinued, but the Calculation Agent does not determine to use a substitute or successor base rate as provided above, then the Calculation Agent will request the principal London office of each of four major reference banks in the London interbank market, selected by the Calculation Agent, to provide such bank’s offered quotation to prime banks in the London interbank market for deposits in U.S. dollars with a term of three months as of 11:00 a.m., London time, on such determination date and in a principal amount equal to an amount that, in the judgment of the Calculation Agent, is representative for a single transaction in U.S. dollars in the relevant market at the relevant time (a “representative amount”). If at least two such quotations are so provided, three-month LIBOR for such Floating Rate Interest Period will be the arithmetic mean of such quotations. If fewer than two such quotations are provided, the Calculation Agent will request each of three major banks in the City of New York to provide such bank’s rate for loans in U.S. dollars to leading European banks with a term of three months as of approximately 11:00 a.m., the City of New York time, on such determination date and in a representative amount. If at least two such rates are so provided, three-month LIBOR for such Floating Rate Period will be the arithmetic mean of such quotations. If fewer than two such rates are so provided, then three-month LIBOR for such Floating Interest Rate Period will be set to equal three-month LIBOR for the then current Floating Rate Interest Period or, in the case of the first Floating Rate Interest Period, 2.17% (resulting in a 5.00% interest rate on the notes for such Floating Rate Interest Period).

The term “Designated LIBOR Page” means the display on Reuters or any successor service, on page LIBOR01 or on any other page as may replace that page on the service, for the purpose of displaying the London interbank rates of U.S. dollars.

The term “Calculation Agent” means the calculation agent appointed by the Company to calculate the interest due with respect to the Notes on each Floating Period Interest Payment Date, which calculation agent shall be appointed on or before the determination date for the first Floating Period Interest Payment Date (and which calculation agent may be the trustee, the Company or one of their respective affiliates). If the Company does not engage a third party to act as the Calculation Agent on or before the determination date for the first Floating Rate Interest Period, the Company will serve as the Calculation Agent and will be responsible for calculating the interest rate for each Floating Rate Interest Period while serving as the Calculation Agent.

The term “Place of Payment” means the place or places where the principal of, or any premium or interest on the notes are payable as provided in or pursuant to the indenture or the notes.

Subordination of the Notes

Our obligation to make any payment on account of the principal of, or interest on, the notes will be subordinate and junior in right of payment to the prior payment in full of all of our senior indebtedness.

“Senior indebtedness” means the principal of, and premium, if any, and interest, including interest accruing after the commencement of any bankruptcy proceeding relating to our Company, on, or substantially similar payments we will make in respect of the following categories of indebtedness, whether that indebtedness is outstanding at the time of execution of the indenture or thereafter incurred, created or assumed:

S-26

However, “senior indebtedness” excludes:

As used above, the term “purchase-money obligations” means indebtedness, obligations evidenced by a note, debenture, bond or other instrument, whether or not secured by a lien or other security interest, issued to evidence the obligation to pay or a guarantee of the payment of, and any deferred obligation for the payment of, the purchase price of property but excluding indebtedness or obligations for which recourse is limited to the property purchased, issued or assumed as all or a part of the consideration for the acquisition of property or services, whether by purchase, merger, consolidation or otherwise, but does not include any trade accounts payable.

S-27

In accordance with the subordination provisions of the indenture and the notes, we are permitted to make payments of accrued and unpaid interest on the notes on the interest payment dates and at maturity and to pay the principal of the notes at maturity unless:

Upon our termination, winding up, liquidation or reorganization, including as a result of any action in any liquidation, reorganization or other insolvency proceeding under the bankruptcy laws or any other applicable insolvency law or upon an assignment for the benefit of our creditors or any other marshalling of our assets and liabilities or otherwise, we must pay to the holders of all of our senior indebtedness the full amounts of principal of, and premium, if any, and interest on, that senior indebtedness before any payment is made on the notes. If, after we have paid the senior indebtedness in full, there are any amounts available for payment of the notes and any of our other indebtedness and obligations ranking equally in right of payment with the notes, then we will use such remaining assets to pay the amounts of principal of, premium, if any, and accrued and unpaid interest on, the notes and such other of our indebtedness and obligations that rank equally in right of payment with the notes. If those assets are insufficient to pay in full the principal of, premium, if any, and interest on the notes and such other indebtedness and obligations, those assets will be applicable ratably to the payment of such amounts owing with respect to the notes and such other indebtedness and obligations.

In the event that we are subject to any termination, winding up, liquidation or reorganization, including pursuant to any liquidation, reorganization or other insolvency proceeding under the bankruptcy or any other insolvency laws, or we have made an assignment for the benefit of our creditors or otherwise marshalled our assets and liabilities, if the holders of the notes receive for any reason any payment on the notes or other distributions of our assets with respect to the notes before all of our senior indebtedness is paid in full, the holders of the notes will be required to return that payment or distribution to the bankruptcy trustee, receiver, liquidating trustee, custodian, assignee, agent or other person making payment of our assets for all our senior indebtedness remaining unpaid until all that senior indebtedness has been paid in full, after giving effect to any other concurrent payment or distribution to the holders of such senior indebtedness.

By reason of the above subordination in favor of the holders of our senior indebtedness, in the event of our bankruptcy or insolvency, holders of our senior indebtedness may receive more, ratably, and holders of the notes may receive less, ratably, than our other creditors.

We have outstanding junior subordinated debentures that relate to outstanding trust preferred securities issued by certain special purpose trusts to which the notes will rank senior in right of payment. We also have outstanding other subordinated notes to which the notes will rank equally in right of payment. In addition, we may incur other indebtedness and obligations, the terms of which provide that such indebtedness ranks either equally or junior in right of payment with or to the notes or promissory notes, bonds, debentures and other evidences of indebtedness of a type that includes the notes. As discussed above, upon our termination, winding up, liquidation or reorganization, including as a result of any liquidation, reorganization or other insolvency proceeding under the bankruptcy laws or any other applicable insolvency law, the indebtedness and obligations ranking equally with the notes will participate ratably in any of our assets remaining after the payment in full of all of our senior indebtedness. In such circumstances, our indebtedness and other obligations junior in right of

S-28

payment to the notes, such as our junior subordinated debentures, will not be entitled to receive any payments until the notes and all of our indebtedness and obligations ranking equally in right of payment to the notes have been paid in full.

All liabilities of Independent Bank, including deposits, and our other subsidiaries, including each subsidiary’s liabilities to general creditors arising during its ordinary course of business or otherwise, will be effectively senior in right of payment to the notes to the extent of the assets of such subsidiary because, as a shareholder of the subsidiary, we do not have any rights to the assets of the subsidiary except if the subsidiary declares a dividend payable to us or if there are assets of the subsidiary remaining after it has discharged its liabilities to its creditors in connection with its liquidation. Over the term of the notes, we will need to rely primarily on dividends paid to us by Independent Bank, which is a regulated financial institution, for the funds necessary to pay the interest on our outstanding debt obligations and to make dividends and other payments on our other securities outstanding now or in the future. With respect to the payment of the principal of the notes at their maturity, we may rely on the funds we receive from dividends paid to us by our subsidiaries, but will likely have to rely on the proceeds of borrowings and other securities we sell to pay the principal amount of the notes. Regulatory rules may restrict Independent Bank’s ability to pay dividends or make other distributions to us or to provide funds to us by other means. As a result of the foregoing, with respect to the assets of each of our subsidiaries, our creditors (including the holders of the notes) are structurally subordinated to the prior claims of creditors of any such subsidiary, including the depositors of Independent Bank, except to the extent that we may be a creditor with recognized claims against any such subsidiary.

As discussed above, neither the notes nor the indenture contains any limitation on the amount of senior indebtedness or other obligations ranking senior to or equally with the indebtedness evidenced by the notes that we, Independent Bank or any of our other subsidiaries may incur. As of September 30, 2017, Independent Bank Group had no senior indebtedness outstanding, $110.0 million of subordinated indebtedness on a gross basis (which was comprised of our other outstanding subordinated notes) outstanding ranking equally with the notes and $31.6 million of junior subordinated indebtedness on a gross basis (which was comprised of our existing junior subordinated debentures underlying outstanding trust preferred securities) outstanding ranking junior to the notes. As of September 30, 2017, and the date of this prospectus supplement, we had in effect a senior revolving credit facility permitting us to borrow up to $50.0 million to be outstanding at any one time. That facility will expire by its terms on October 19, 2018. Any indebtedness and liabilities of Independent Bank or our other subsidiaries is not a part of our senior indebtedness. The notes will be effectively subordinate to all of the existing and future indebtedness and liabilities, including deposit liabilities, of our subsidiaries, including Independent Bank. As of September 30, 2017, Independent Bank and our other subsidiaries had outstanding indebtedness, total deposits and other liabilities of $7.6 billion, excluding intercompany liabilities, all of which is structurally superior in right of payment to the notes.

Optional Redemption and Redemption Upon Special Events

We may redeem the notes, at our sole option, beginning with the interest payment date of December 31, 2022, and on any Interest Payment Date thereafter, in whole or in part, at a redemption price equal to 100% of the principal amount of the notes to be redeemed, plus accrued and unpaid interest to, but excluding, the date of redemption, subject to prior approval of the Federal Reserve Board, to the extent that such approval is required. If we elect to redeem the notes, we will be required to notify the trustee of the aggregate principal amount of notes to be redeemed and the redemption date. If fewer than all of the notes are to be redeemed, the trustee is required to select the notes to be redeemed equally, by lot or in a manner it deems fair and appropriate. The notes are not subject to repayment at the option of the holders. The notes may not otherwise be redeemed by us prior to the scheduled maturity of the notes, except we may, at our option, redeem the notes before the scheduled maturity of the notes in whole, but not in part, at any time after the date on which we sell the notes to investors, at any time within 90 days after the occurrence of any of the following:

(1) a “Tax Event,” which is defined in the indenture to mean the receipt by us of an opinion of independent tax counsel to the effect that (a) an amendment to or change (including any announced prospective amendment or

S-29

change) in any law or treaty, or any regulation thereunder, of the United States or any of its political subdivisions or taxing authorities, (b) a judicial decision, administrative action, official administrative pronouncement, ruling, regulatory procedure, regulation, notice or announcement, including any notice or announcement of intent to adopt or promulgate any ruling, regulatory procedure or regulation, (c) an amendment to or change in any official position with respect to, or any interpretation of, an administrative or judicial action or a law or regulation of the United States that differs from the previously generally accepted position or interpretation, or (d) a threatened challenge asserted in writing in connection with an audit of our federal income tax returns or positions or a similar audit of any of our subsidiaries or a publicly known threatened challenge asserted in writing against any other taxpayer that has raised capital through the issuance of securities that are substantially similar to the notes, in each case, occurring or becoming publicly known on or after the date of original issuance of the notes, resulting in more than an insubstantial risk that the interest payable on the notes is not, or within 90 days of receipt of such opinion of tax counsel, will not be, deductible by us, in whole or in part, for U.S. federal income tax purposes;

(2) a “Tier 2 Capital Event,” which is defined in the indenture to mean the receipt by us of an opinion of independent bank regulatory counsel to the effect that, as a result of (a) any amendment to, or change (including any announced prospective change) in, the laws or any regulations thereunder of the United States or any rules, guidelines or policies of an applicable regulatory authority for the Company or (b) any official administrative pronouncement or judicial decision interpreting or applying such laws or regulations, which amendment or change is effective or which pronouncement or decision is announced on or after the date of original issuance of the notes, the notes do not constitute, or within 90 days of the date of such opinion will not constitute, Tier 2 capital (or its then equivalent if we were subject to such capital requirement) for purposes of capital adequacy guidelines of the Federal Reserve Board (or any successor regulatory authority with jurisdiction over bank holding companies), as then in effect and applicable to us; or

(3) our becoming required to register as an investment company pursuant to the Investment Company Act of 1940, as amended.

Any such redemption of the notes will be at a redemption price equal to the principal amount of the notes plus accrued and unpaid interest to, but excluding, the date of redemption. Any redemption, call or repurchase of the notes would require prior approval of the Federal Reserve Board.

Our election to redeem any of the notes upon the occurrence of any of the enumerated events above will be provided to the trustee at least 60 days prior to the redemption date. In case of any such election, notice of redemption must be provided at any time after giving not less than 30 nor more than 60 days’ notice of such redemption to the holders of the notes.

The Notes Are Intended to Qualify as Tier 2 Capital

We intend to treat the notes as Tier 2 capital under the capital rules established by the Federal Reserve Board for bank holding companies and the guidelines of the Federal Reserve Board for bank holding companies under the Basel III framework. The rules set forth specific criteria for instruments to qualify as Tier 2 capital. Among other things, the notes must:

S-30

Events of Default; Limitation on Suits

Under the indenture, an event of default will occur if we fail to pay accrued and unpaid interest on the notes and any notes of the same series offered in the future and such failure continues for 30 days, we fail to pay principal of any notes of that series when due, whether at maturity or upon redemption, or we default in the performance of any other covenant or warranty contained in the indenture, other than a covenant added to the indenture solely for the benefit of any other series of subordinated debt securities issued under the indenture, and such default continues for 90 days after written notice as provided in the indenture. In addition, an event of default will occur upon the entry of a decree or order for relief in respect of the Company by a court having jurisdiction in the premises in an involuntary case or proceeding under Chapter 7 (liquidation) or Chapter 11 (reorganization) of the U.S. Bankruptcy Code as now or hereafter in effect, and such decree or order continues unstayed and in effect for a period of 60 consecutive days or if we commence a bankruptcy or insolvency proceeding or consent to the entry of an order in an involuntary proceeding under Chapter 7 (liquidation) or Chapter 11 (reorganization) of the U.S. Bankruptcy Code as now or hereafter in effect, each of which events of default we refer to as an “insolvency event of default.”

Neither the trustee nor the holders of the notes will have the right to accelerate the maturity of the notes in the case of our failure to pay the principal of, or interest on, the notes or our nonperformance of any other covenant or warranty under the notes or the indenture. Nevertheless, during the continuation of such an event of default under the notes, the trustee may, subject to certain limitations and conditions, seek to enforce its rights and the rights of the holders of notes to regularly scheduled payments of interest and the payment of principal at the scheduled maturity of the notes, as well as the performance of any covenant or agreement in the indenture. Any such rights to receive payment of such amounts under the notes remain subject to the subordination provisions of the notes as discussed above under “—Subordination of the Notes.”

If an insolvency event of default occurs and is continuing, the principal amount and accrued and unpaid interest on the notes shall become immediately due and payable, without the need for any action on the part of the holders of the notes or the trustee, subject to the broad equity powers of a federal bankruptcy court and the determination by that court of the nature and status of the payment claims of the holders of the notes. At any time after acceleration with respect to the notes has occurred, but before a judgment or decree for payment of the money due has been obtained, the holders of a majority in aggregate principal amount of outstanding notes of the series of our subordinated notes which the notes are a part and other affected series of securities issued under the indenture, voting as one class, may waive all defaults and rescind and annul any acceleration occurring as to any and all securities of such series, including the notes, but only if (1) we have paid or deposited with the trustee a sum of money sufficient (a) to pay to the holders of the outstanding securities of all affected series of securities established under the indenture, including the notes, (i) all overdue installments of any interest that have become due otherwise than by such declaration of acceleration, (ii) the principal of and any premium that have become due otherwise than by such declaration of acceleration and, to the extent permitted by applicable law, interest thereon at the rate of interest borne by these securities and (iii) to the extent permitted by applicable law, interest upon installments of any interest, if any, that have become due otherwise than by such declaration of acceleration at the rate of interest borne by these securities and (b) to pay all sums paid or advanced by the trustee under the indenture and the reasonable compensation, expenses, disbursements and advances of the trustee, its agents and counsel and all other amounts due the trustee; and (2) all events of default with respect to the notes other than the nonpayment of the principal of, or any premium and interest on, the notes that shall have become due solely by such acceleration, shall have been cured or waived as provided in the indenture. Even in the event of an acceleration of the maturity of the notes upon the occurrence of an insolvency event, the rights of the holders of the notes to receive payment of the principal of, and accrued and unpaid interest on, the notes remain subject to the subordination provisions of the notes as discussed above under “—Subordination of the Notes.”

S-31

The indenture provides that, subject to the duty of the trustee upon the occurrence of an event of default to act with the required standard of care, the trustee will be under no obligation to exercise any of its rights or powers under the indenture at the request or direction of any of the holders of notes unless such holders shall have offered to the trustee indemnity or security reasonably satisfactory to the trustee against the costs, expenses and liabilities that may be incurred by it in complying with such request or direction. Subject to certain provisions in the indenture, the holders of a majority in principal amount of the notes outstanding from time to time will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee with respect to the notes.

Clearance and Settlement

DTC, in this capacity, will act as securities depositary for the notes. The notes will be issued only as fully registered securities registered in the name of Cede & Co. (DTC’s partnership nominee) or such other name as may be requested by an authorized representative of DTC. A fully registered global note, representing the total aggregate principal amount of the notes that are issued and sold, will be executed and deposited with DTC and will bear a legend disclosing the restrictions on exchanges and registration of transfer referred to below. See “Book Entry Issuance” in the accompanying prospectus for more information concerning DTC and its facilitation of clearance and post-trade settlement of transactions among its participants.

The laws of some jurisdictions may require that some purchasers of securities take physical delivery of securities in definitive form. These laws may impair the ability to transfer beneficial interests in the notes, so long as the corresponding securities are represented by global notes.

Purchases of securities under the DTC system must be made by or through direct participants in DTC, who will receive a credit for the securities on DTC’s records. The ownership interest of each beneficial owner of securities will be recorded on the direct or indirect participants’ records. Beneficial owners will not receive written confirmation from DTC of their purchase. Beneficial owners are, however, expected to receive written confirmations providing details of the transaction, as well as periodic statements of their holdings, from the direct or indirect participant through which the beneficial owner entered into the transaction. Under a book-entry format, holders may experience some delay in their receipt of payments made with respect to the notes, as such payments will be forwarded by the paying agent for the notes to Cede & Co., as nominee for DTC. DTC will forward the payments to its participants, who will then forward them to indirect participants or holders. Beneficial owners of securities other than DTC or its nominees will not be recognized by the relevant registrar, transfer agent, paying agent or trustee as registered holders of the notes entitled to the benefits of the indenture. Beneficial owners that are not participants will be permitted to exercise their rights only indirectly through and according to the procedures of participants and, if applicable, indirect participants.

To facilitate subsequent transfers, all securities deposited by direct participants with DTC are registered in the name of DTC’s partnership nominee, Cede & Co., or such other name as may be requested by an authorized representative of DTC. The deposit of securities with DTC and their registration in the name of Cede & Co. or such other DTC nominee do not result in any change in beneficial ownership of those securities. DTC does not have, and is not anticipated to have, any knowledge of the actual beneficial owners of the notes, as DTC’s records reflect only the identity of the direct participants to whose accounts the notes are credited, which may or may not be the beneficial owners. The direct and indirect participants will remain responsible for keeping account of their holdings on behalf of their customers.

Conveyance of redemption notices and other communications by DTC to direct participants, by direct participants to indirect participants, and by direct and indirect participants to beneficial owners will be governed by arrangements among them, subject to any statutory or regulatory requirements as may be in effect from time to time. If less than all of the securities of any class are being redeemed, DTC will determine the amount of the interest of each direct participant to be redeemed in accordance with its then current procedures.

S-32

DTC may discontinue providing its services as securities depositary with respect to the notes at any time by giving reasonable notice to the issuer or its agent. Under these circumstances, in the event that a successor securities depositary is not obtained, certificates for the notes are required to be printed and delivered. We may decide to discontinue the use of the system of book-entry-only transfers through DTC (or a successor securities depositary). In that event, certificates for the notes will be printed and delivered to DTC.

As long as DTC or its nominee is the registered owner of the global note representing the notes, DTC or its nominee, as the case may be, will be considered the sole owner and holder of that global note and all notes represented by that global note for all purposes under the instruments governing the rights and obligations of holders of such securities. Except in the limited circumstances referred to above, owners of beneficial interests in the global note:

All redemption proceeds, payments of principal of, and interest on, the notes represented by the global note and all transfers and deliveries of such global note will be made to DTC or its nominee, as the case may be, as the registered holder of the global note. DTC’s practice is to credit its direct participants’ accounts upon DTC’s receipt of funds and corresponding detail information from the issuer or its agent, on the payment date in accordance with their respective holdings shown on DTC’s records. Payments by participants to beneficial owners of the notes will be governed by standing instructions and customary practices of those participants, as is the case with securities held for the accounts of customers in bearer form or registered in “street name,” and will be the responsibility of that participant and not of DTC, the depositary, the issuer, the trustee or any of their respective agents, subject to any statutory or regulatory requirements as may be in effect from time to time. Payment of redemption proceeds and payments of principal of, or interest on, the notes to Cede & Co. (or such other nominee as may be requested by an authorized representative of DTC) are the responsibility of the issuer or its agent, disbursement of such payments to direct participants will be the responsibility of DTC, and disbursement of such payments to the beneficial owners of the notes will be the responsibility of direct and indirect participants.

Ownership of beneficial interests in the global note will be limited to participants or persons that may hold beneficial interests through institutions that have accounts with DTC or its nominee. Ownership of beneficial interests in the global note will be shown only on, and the transfer of those ownership interests will be effected only through, records maintained by DTC or its nominee, with respect to participants’ interests, or any participant, with respect to interests of persons held by the participant on their behalf. Payments, transfers, deliveries, exchanges, redemptions and other matters relating to beneficial interests in the global note may be subject to various policies and procedures adopted by DTC from time to time. None of the Company, the trustee or any agent for any of them will have any responsibility or liability for any aspect of DTC’s or any direct or indirect participant’s records relating to, or for payments made on account of, beneficial interests in the global note, or for maintaining, supervising or reviewing any of DTC’s records or any direct or indirect participant’s records relating to these beneficial ownership interests.

Although DTC has agreed to the foregoing procedures in order to facilitate transfer of interests in the global note among participants, DTC is under no obligation to perform or continue to perform these procedures, and these procedures may be discontinued at any time. Neither the Company nor the trustee will have any responsibility for the performance by DTC or its direct participants or indirect participants under the rules and procedures governing DTC or the standby instructions or customary procedures of the participants.

S-33

Because DTC can act only on behalf of direct participants, who in turn act only on behalf of direct or indirect participants, and certain banks, trust companies and other persons approved by it, the ability of a beneficial owner of the notes to pledge them to persons or entities that do not participate in the DTC system may be limited due to the unavailability of physical certificates for the notes.

DTC has advised us that it will take any action permitted to be taken by a registered holder of any securities under the indenture only at the direction of one or more participants to whose accounts with DTC the relevant securities are credited.

The information in this section concerning DTC and its book-entry system has been obtained from sources that we believe to be accurate, but we assume no responsibility for the accuracy thereof.

Same-Day Settlement and Payment

Settlement for the notes will be made in immediately available funds. The notes will trade in DTC’s Same-Day Funds Settlement System until maturity and, therefore, DTC will require secondary trading activity in the notes to be settled in immediately available funds. Secondary trading in long-term notes and notes of corporate issuers is generally settled in clearing house or next-day funds. No assurance can be given as to the effect, if any, of settlement in immediately available funds on trading activity of the notes.

Regarding the Indenture Trustee

Wells Fargo Bank, National Association, acts as trustee under the indenture pursuant to which our other subordinated notes have been issued and the notes will be issued. From time to time, we and some of our subsidiaries may maintain deposit accounts and conduct other banking transactions, including lending transactions, with the trustee in the ordinary course of business. Wells Fargo is also the trustee under the indenture pursuant to which we may issue our debt securities that will be senior indebtedness for purposes of the notes.

Upon the occurrence of an event of default or an event which, after notice or lapse of time or both, would become an event of default under the notes, or upon the occurrence of a default under another indenture under which Wells Fargo serves as trustee, the trustee may be deemed to have a conflicting interest with respect to the other debt securities as to which we are not in default for purposes of the Trust Indenture Act and, accordingly, may be required to resign as trustee under the indenture. In that event, we would be required to appoint a successor trustee.

Wells Fargo also serves as the transfer agent for our common stock.

S-34

U.S. FEDERAL INCOME TAX CONSIDERATIONS

For a general discussion of certain U.S. federal income tax consequences relating to the purchase, ownership and disposition of the notes, including the requirements and certification rules for non-U.S. holders of the notes, please see the discussion under “U.S. Federal Income Tax considerations” in the accompanying prospectus. In addition to the U.S. federal income tax consequences described under “U.S. Federal Income Tax Considerations” in the accompanying prospectus, the following specific consequences apply to the notes offered by this prospectus supplement and the accompanying prospectus.

Interest and Original Issue Discount on the Notes

The notes are expected to be treated as variable rate debt instruments for U.S. federal income tax purposes. Under this characterization, payments treated as qualified stated interest (as defined in the accompanying prospectus) on the notes will generally be taxable to U.S. holders (as defined in the accompanying prospectus) as ordinary interest income at the time such interest payments are accrued or received, depending on the U.S. holder’s regular method of accounting for U.S. federal income tax purposes.

Based upon current market conditions and the manner in which the interest rates on the notes are determined, we expect all interest on the notes will be treated as qualified stated interest and the notes will be treated as having been issued with no more than a de minimis amount of original issue discount.

S-35

UNDERWRITING

We have entered into an underwriting agreement with Piper Jaffray & Co. and U.S. Bancorp Investments, Inc. with respect to the notes being offered pursuant to this prospectus supplement. Subject to certain conditions, each underwriter has agreed, severally but not jointly, to purchase the aggregate principal amount of notes in this offering set forth next to its name in the following table.

The underwriting agreement provides that the obligations of the several underwriters to purchase the notes offered hereby are subject to certain conditions precedent and that the underwriters are obligated to purchase all of the notes offered by this prospectus supplement if any of the notes are purchased.

We have agreed to indemnify the underwriters against some specified types of liabilities, including liabilities under the Securities Act of 1933, as amended, and to contribute to payments the underwriters may be required to make in respect of any of these liabilities.

Discounts

The following table shows the per note and total underwriting discounts and commissions we will pay the underwriters.

Notes sold by the underwriters to the public will be offered at the public offering price set forth on the cover of this prospectus supplement. If all of the notes are not sold at their applicable initial offering prices, the underwriters may change the offering prices and the other selling terms. The offering of the notes by the underwriters is subject to receipt and acceptance and subject to the underwriters’ right to reject any order in whole or in part.

The expenses of the offering, not including the underwriting discounts and commissions, are estimated at $175,000 and are payable by us. We also have agreed to reimburse the underwriters up to $75,000 for their expenses including reasonable attorney’s fees and out of pocket expenses related to the offering. In accordance with FINRA Rule 5110, this reimbursed fee is deemed underwriting compensation for this offering.

The representatives of the underwriters have advised us that the underwriters do not intend to confirm sales to any account over which they exercise discretionary authority.

New Issuance of Notes

There is currently no public trading market for the notes. In addition, we have not applied and do not intend to apply to list the notes on any national securities exchange or to have the notes quoted on an automated dealer quotation system. The underwriters have advised us that they intend to make a market in the notes. However, they are not obligated to do so and may discontinue any market-making in the notes at any time in their sole discretion and without prior notice. Therefore, we cannot assure you that a liquid trading market for the notes will develop or continue, that you will be able to sell your notes at a particular time, or that the price that you

S-36

receive when you sell will be favorable. If an active public trading market for the notes does not develop, the market price and liquidity of the notes may be adversely affected. If the notes are traded, they may trade at a discount from their initial offering price, depending on prevailing interest rates, the market for similar securities, our operating performance and financial condition, general economic conditions and other factors.

No Sales of Similar Securities

We have agreed, for a period beginning on the date of the underwriting agreement and continuing to and including the closing date of the offering contemplated hereby, that we will not, without the prior written consent of the representatives of the underwriters, directly or indirectly, issue, sell, offer or contract to sell, grant any option for the sale of, or otherwise transfer or dispose of, any debt securities, including any guarantee of such securities, or any securities convertible into or exchangeable for or representing the right to receive such securities, other than the notes.

Settlement

Delivery of the notes is expected to be made against payment therefor on or about December 19, 2017, which is the 3rd business day following the date of pricing of the notes (such settlement being referred to as “T+3”). Under Rule 15c6-1 of the Exchange Act, trades in the secondary market generally are required to settle in two business days unless the parties to any such trade expressly agree otherwise. Accordingly, purchasers who wish to trade the notes on the date of pricing of the notes will be required, by virtue of the fact that the notes initially will settle in T+3, to specify an alternate settlement cycle at the time of any such trade to prevent failed settlement and should consult their own advisers.

Price Stabilization; Short Positions

In connection with this offering of the notes, the underwriters may engage in overallotment, stabilizing transactions and syndicate covering transactions. Overallotment involves sales in excess of the offering size, which may create a short position for the underwriters. Stabilizing transactions involve bids to purchase the notes in the open market for the purpose of pegging, fixing, or maintaining the price of the notes. Syndicate covering transactions involve purchases of the notes in the open market after the distribution has been completed in order to cover short positions. The underwriters may also impose a penalty bid. This occurs when a particular underwriter repays to the other underwriters a portion of the underwriting discount received by it because the representative has repurchased notes sold by or for the account of such underwriter in stabilizing or syndicate covering transactions. Stabilizing transactions and syndicate covering transactions, and together with the imposition of a penalty bid, may cause the price of the notes to be higher than it would otherwise be in the absence of those transactions. If the underwriters engage in stabilizing or syndicate covering transactions, they may discontinue them at any time.

Neither we nor any of the underwriters make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of the notes. In addition, neither we nor any of the underwriters make any representation that the underwriters will engage in these transactions or that these transactions, once commenced, will not be discontinued without notice.

Electronic Distribution

This prospectus supplement and the accompanying prospectus may be made available in electronic format on websites or through other online services maintained by the underwriters or their affiliates.

Other than the prospectus supplement and the accompanying prospectus in electronic format, information on such websites and any information contained in any other website maintained by the underwriters or their

S-37

affiliates is not part of this prospectus supplement or our registration statement of which the related prospectus forms a part, has not been approved or endorsed by us or the underwriters in their capacity as underwriters and should not be relied on by investors.

Other Relationships

Some of the underwriters and their affiliates have engaged in, and may in the future engage in, investment banking and other commercial dealings in the ordinary course of business with us or our affiliates. They have received, or may in the future receive, customary fees and commissions for these transactions.

In addition, in the ordinary course of their business activities, the underwriters and their affiliates may make or hold a broad array of investments including serving as counterparties to certain derivative and hedging arrangements and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers. Such investments and securities activities may involve securities and/or instruments of ours or our affiliates. If any of the underwriters or their affiliates has a lending relationship with us, they may hedge their credit exposure to us consistent with their customary risk management policies. These underwriters and their affiliates could hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities, including potentially the notes offered hereby. Any such credit default swaps or short positions could adversely affect future trading prices of the notes offered hereby. The underwriters and their affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or financial instruments and may hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

Other Matters

Other than in the United States, no action has been taken by us or the underwriters that would permit a public offering of the notes offered by this prospectus supplement in any jurisdiction in which action for that purpose is required. The notes offered by this prospectus supplement may not be offered or sold, directly or indirectly, nor may this prospectus supplement, the accompanying prospectus or any other offering material or advertisements in connection with the offer and sale of any such securities be distributed or published in any jurisdiction, except under circumstances that will result in compliance with the applicable rules and regulations of that jurisdiction. We and the underwriters require that the persons into whose possession this prospectus supplement comes inform themselves about, and observe any restrictions relating to, the offering and the distribution of this prospectus supplement. This prospectus supplement does not constitute an offer to sell or a solicitation of an offer to buy any securities offered by this prospectus supplement in any jurisdiction in which such an offer or a solicitation is unlawful.

S-38

LEGAL MATTERS

The validity of the notes will be passed upon for us by Andrews Kurth Kenyon LLP, Dallas, Texas. Certain legal matters in connection with this offering will be passed upon for the underwriters Covington & Burling LLP, Washington, D.C.

EXPERTS

The consolidated financial statements of Independent Bank Group, Inc. appearing in Independent Bank Group, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2016, have been audited by RSM US LLP, an independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein and in the accompanying prospectus by reference. Such consolidated financial statements are incorporated herein and in the accompanying prospectus by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

The consolidated financial statements for the years ended December 31, 2016 and 2015, of Carlile Bancshares, Inc., which was acquired by the Company on April 1, 2017, and appearing in Amendment No. 1 to the Company’s Current Report on Form 8 K, filed with the SEC on June 6, 2017, have been audited by Crowe Horwath, LLP, independent auditors, as set forth in their report thereon, included therein, and incorporated herein and in the accompanying prospectus by reference. Such consolidated financial statements are incorporated herein and in the accompanying prospectus by reference upon such report given on the authority of such firm as experts in accounting and auditing.

S-39

PROSPECTUS

1600 Redbud Boulevard, Suite 400

McKinney, Texas 75069-3257

(972) 562-9004

DEBT SECURITIES, PREFERRED STOCK, COMMON STOCK, AND UNITS OF SECURITIES

By this prospectus, Independent Bank Group, Inc. may offer from time to time:

In addition, this prospectus may be used to offer securities for the account of selling securityholders.

When Independent Bank Group, Inc. or selling securityholders offer our securities for sale, we or they will provide you with a prospectus supplement describing the terms of the specific issue of our securities being offered, including the price at which those securities are being offered to the public.

We or any selling securityholders may offer and sell these securities to or through one or more underwriters, dealers and agents, or directly to purchasers, on a continuous or delayed basis, as described in more detail below under “Plan of Distribution” or in any accompanying prospectus supplement

You should read this prospectus and any accompanying prospectus supplement carefully before you decide to invest. This prospectus may not be used to sell securities unless it is accompanied by a prospectus supplement that further describes the securities being offered to you.

Our common stock is listed for trading on The Nasdaq Stock Market LLC Global Select Market, or NASDAQ Global Select Market, under the symbol “IBTX.” We have not yet determined whether any of the other securities that may be offered by this prospectus will be listed for trading on any exchange. If we decide to apply to list any such securities for trading on a securities exchange upon their issuance, the prospectus supplement relating to those securities will disclose the exchange on which we will apply to have those securities listed for trading.

Investing in our securities involves risks. See “Risk Factors” in our most recent Annual Report on Form 10-K, which is incorporated herein by reference, and in any of our subsequently filed quarterly and current reports that are incorporated herein by reference. We may include specific risk factors in an applicable prospectus supplement under the heading “Risk Factors.” You should carefully read this prospectus together with the documents we incorporate by reference and any accompanying prospectus supplement before you invest in our securities.

This prospectus is not an offer to sell any securities other than the securities offered hereby. This prospectus is not an offer to sell securities in any jurisdictions or in any circumstances in which such an offer is unlawful.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The offered securities are not savings accounts, deposits or other obligations of any bank or savings association and are not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

The date of this prospectus is June 16, 2017.

You should rely only on the information contained in or incorporated by reference in this prospectus and in the applicable prospectus supplement deciding whether to invest. We have not, and no selling securityholder has, authorized anyone to give oral or written information about this offering, our Company, or the securities offered hereby that is different from the information included or incorporated by reference in this prospectus. If anyone provides you with different information, you should not rely on it. You should assume that the information contained in this prospectus is accurate only as of the date on the front cover of this prospectus. Our business, financial condition, results of operations and prospects may have changed since that date.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or the SEC, using the automatic “shelf” registration process offered to “well-known seasoned issuers” as described in Rule 405 of the SEC under the Securities Act of 1933, or the Securities Act. Under this automatic shelf registration statement, we and selling securityholders may offer and sell, from time to time and in one or more offerings, either separately or together, shares of our common stock, shares of one or more series of our preferred stock, senior debt securities of one or more series, and subordinated debt securities of one or more series and unit purchase agreements as described in this prospectus and an applicable prospectus supplement.

Each time we or selling securityholders sell securities we and the selling securityholders will provide a prospectus supplement containing specific information about the terms of the securities being offered thereby. The prospectus supplement may include a discussion of any risk factors or other special considerations that apply to those securities. The prospectus supplement may also add, update or change the information in this prospectus. If there is any inconsistency between the information in this prospectus (including the information incorporated by reference herein) and information in any prospectus supplement, you should rely on the information in the applicable prospectus supplement, which will be controlling. You should carefully read both this prospectus and the applicable prospectus supplement together with additional information described under the heading “Where You Can Find More Information” or incorporated herein by reference as described under the heading “Incorporation of Certain Documents by Reference.”

References in this prospectus to “our Company,” “we,” “us” and “our” are to Independent Bank Group, Inc. In this prospectus, we sometimes refer to the debt securities, common stock, preferred stock, unit purchase agreements we may offer and the securities that may be offered by selling securityholders collectively as “offered securities.”

ABOUT INDEPENDENT BANK GROUP, INC.

Independent Bank Group, Inc. is incorporated in Texas and is a bank holding company registered under the Bank Holding Company Act of 1956. We are based in McKinney, Texas, and conduct our operations primarily through our bank subsidiary, Independent Bank. Independent Bank provides a wide range of relationship-driven commercial banking products and services tailored to meet the needs of businesses, professionals and individuals from banking offices located throughout Texas, including in the Dallas-Fort Worth, Austin/Central Texas, and Houston areas, as well as in Colorado. Our common stock is traded on the NASDAQ Global Select Market under the symbol “IBTX.”

Our principal executive offices are located at 1600 Redbud Boulevard, Suite 400, McKinney, Texas 75069-3257. Our telephone number is (972) 562-9004. Our website is www.ibtx.com. References to our website and those of our subsidiaries are not intended to be active links and the information on such websites is not, and you must not consider that information to be, a part of this prospectus.

RISK FACTORS

An investment in our securities involves certain risks. Before making an investment decision, you should carefully read and consider the risk factors set forth in our most recent Annual Report on Form 10-K filed with the SEC (our “Latest Form 10-K”), under the heading “Risk Factors,” as well as any updated or additional disclosure about risk factors included in any of our Quarterly Reports on Form 10-Q, Current Reports on Form 8-K or other filings that we have made with the SEC since the date of the Latest Form 10-K that are incorporated by reference in this prospectus. We may include specific risk factors in an applicable prospectus supplement under the heading “Risk Factors.” Additional risks and uncertainties of which we are not aware or that we believe are not material at the time could also materially and adversely affect our business, financial condition, results of operations or liquidity. In any case, the value of the securities offered by means of this prospectus and any applicable prospectus supplement could decline and you could lose all or part of your investment.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain statements contained in this prospectus that are not statements of historical fact constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks and uncertainties and are made pursuant to the safe harbor provisions of Section 27A of the Securities Act. These forward-looking statements include information about our possible or assumed future results of operations, including our future revenues, income, expenses, provision for taxes, effective tax rate, earnings per share and cash flows, our future capital expenditures and dividends, our future financial condition and changes therein, including changes in our loan portfolio and allowance for loan losses, our future capital structure or changes therein, the plan and objectives of management for future operations, our future or proposed acquisitions, the future or expected effect of acquisitions on our operations, results of operations and financial condition, our future economic performance and the statements of the assumptions underlying any such statement. Such statements are typically, but not exclusively, identified by the use in the statements of words or phrases such as “aim,” “anticipate,” “estimate,” “expect,” “goal,” “guidance,” “intend,” “is anticipated,” “is estimated,” “is expected,” “is intended,” “objective,” “plan,” “projected,” “projection,” “will affect,” “will be,” “will continue,” “will decrease,” “will grow,” “will impact,” “will increase,” “will incur,” “will reduce,” “will remain,” “will result,” “would be,” variations of such words or phrases (including where the word “could,” “may” or “would” is used rather than the word “will” in a phrase) and similar words and phrases indicating that the statement addresses some future result, occurrence, plan or objective. The forward-looking statements that we make are based on our current expectations and assumptions regarding its business, the economy, and other future conditions. Because forward-looking statements relate to future results and occurrences, they are subject to

1

inherent uncertainties, risks, and changes in circumstances that are difficult to predict. Many possible events or factors could affect our future financial results and performance and could cause those results or performance to differ materially from those expressed in the forward-looking statements. These possible events or factors include, but are not limited to:

2

We urge you to consider all of these risks, uncertainties and other factors carefully in evaluating all such forward-looking statements made by us. As a result of these and other matters, including changes in facts, assumptions not being realized or other factors, the actual results relating to the subject matter of any forward-looking statement may differ materially from the anticipated results expressed or implied in that forward-looking statement. Any forward-looking statement made in this prospectus or made by us in any report, filing, document or information incorporated by reference in this prospectus, speaks only as of the date on which it is made. We undertake no obligation to update any such forward-looking statement, whether as a result of new information, future developments or otherwise, except as may be required by law.

A forward-looking statement may include a statement of the assumptions or bases underlying the forward-looking statement. We believe that these assumptions or bases have been chosen in good faith and that they are reasonable. However, we caution you that assumptions as to future occurrences or results almost always vary from actual future occurrences or results, and the differences between assumptions and actual occurrences and

3

results can be material. Therefore, we caution you not to place undue reliance on the forward-looking statements contained in this prospectus or incorporated by reference herein.

RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO

COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS

Our historical ratios of earnings to fixed charges and earnings to combined fixed charges and preferred stock dividends for the periods indicated are set forth in the table below. As of March 31, 2017, we did not have any shares of preferred stock outstanding. For the period April 15, 2014, through January 14, 2016, we had 23,938.35 shares of our Series A Preferred Stock that were issued and outstanding. Such shares of Series A Preferred Stock were redeemed on January 14, 2016.

The ratio of earnings to fixed charges is computed by dividing (i) income from continuing operations before income taxes and fixed charges by (ii) total fixed charges. The ratio of earnings to combined fixed charges and preferred stock dividends is computed by dividing (y) income from continuing operations before income taxes and fixed charges by (z) total fixed charges and preferred stock dividends.

For purposes of computing these ratios:

USE OF PROCEEDS

Unless otherwise indicated in the applicable prospectus supplement, we expect to use the net proceeds from the sale of offered securities by us for general corporate purposes, including:

4

The prospectus supplement with respect to an offering of offered securities may identify different or additional uses for the proceeds of that offering.

Except as otherwise stated in an applicable prospectus supplement, pending the application of the net proceeds from the sale of offered securities, we expect to either deposit such net proceeds in deposit accounts or invest them in short-term obligations.

We will not receive proceeds from sales of securities by selling securityholders except as otherwise stated in an applicable prospectus supplement.

THE SECURITIES WE MAY OFFER

The descriptions of the securities contained in this prospectus, together with the applicable prospectus supplements, summarize certain material terms and provisions of the various types of securities that we or selling securityholders may offer. The particular material terms of the securities offered by a prospectus supplement, to the extent not described in this prospectus, will be described in that prospectus supplement. If indicated in the applicable prospectus supplement, the terms of the offered securities may differ from the terms summarized below. The prospectus supplement will also supplement, where applicable, material U.S. federal income tax considerations relating to the offered securities, and will contain information regarding the securities exchange, if any, on which the offered securities will be listed. The descriptions of our securities being offered appearing herein and in the applicable prospectus supplement do not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of the actual documents that govern those securities and whose terms are summarized herein and in the applicable prospectus supplement, because those documents, and not the summaries, define your rights as holders of the relevant securities. For more information, please review the forms of these documents, which are or will be filed with the SEC and will be available as described under the heading “Where You Can Find More Information” below.

We may offer and sell from time to time, in one or more offerings, the following:

Selling securityholders may offer and sell from time to time, in one or more offerings, shares of our common stock or other securities owned by the selling securityholders.

DESCRIPTION OF DEBT SECURITIES

General

We may issue senior debt securities and subordinated debt securities, which in each case will be unsecured, direct, general obligations of our Company.

The senior debt securities will rank equally in right of payment with all of our other unsecured and unsubordinated debt. The subordinated debt securities will be subordinate and junior in right of payment to our senior indebtedness, including our senior debt securities as described below under “—Subordinated Debt

5

Securities” and in the prospectus supplement applicable to any subordinated debt securities that we may offer. For purposes of the descriptions under the heading “Description of Debt Securities,” we may refer to the senior debt securities and the subordinated debt securities collectively as the “debt securities.” The debt securities will be effectively subordinated to the creditors and preferred equity holders of our subsidiaries, if any.

We will issue senior debt securities under a senior debt indenture, dated June 25, 2014, and issue subordinated debt securities under a subordinated debt indenture, dated June 25, 2014, which indentures will be, in each case, between us and Wells Fargo Bank, National Association, in its capacity as the indenture trustee. We refer to the senior debt indenture or subordinated debt indenture, together with any applicable supplemental indentures thereto, in this prospectus as an “indenture” and collectively as the “indentures.” The indentures permit one or more series of senior debt securities or subordinated debt securities, as the case may be, to be established and issued thereunder. Any such series of senior debt securities or subordinated debt securities and their terms and conditions will be established by means of the adoption of a supplemental indenture, the adoption of a resolution of our board of directors or the adoption of a resolution of our board of directors and the action of certain officers of our Company acting pursuant to authority delegated to them by such resolution of the board and evidenced by an officers’ certificate setting forth the terms and conditions of the series of debt securities established by that resolution and the action of such authorized officers. Generally, multiple series of debt securities will vary from one another with regard to the rate at which interest accrues on such debt securities and the term of such debt securities, and the senior debt securities and subordinated debt securities will vary from one another with regard to the priority of payment.

The indentures meet the requirements of the Trust Indenture Act of 1939, as amended, or the “Trust Indenture Act” and will be qualified under and governed by the Trust Indenture Act. The trustee meets the requirements of the Trust Indenture Act for trustees under indentures being qualified under the Trust Indenture Act.

The descriptions under the heading “Description of Debt Securities” relating to the senior debt securities and subordinated debt securities and the indentures are summaries of their provisions. The summaries are not complete and are qualified in their entirety by reference to the indentures and senior and subordinated debt securities and the further descriptions in the applicable prospectus supplement. A copy of each indenture has been filed with the SEC and incorporated by reference as an exhibit to the registration statement that includes this prospectus and will be available for review as described under the heading “Where You Can Find More Information” above. We will file a copy of each supplemental indenture, board resolution and board resolution and related officers’ certificate establishing a series of debt securities and setting the respective series’ terms and conditions with the SEC in connection with the offer and sale of the first debt securities of such series to be offered and sold and will file the form of debt security representing the debt securities of such series with the SEC in connection with the offering of such debt securities. Whenever we refer in this prospectus or in any prospectus supplement to particular sections or defined terms of an indenture, those sections or defined terms are incorporated by reference in this prospectus or in the prospectus supplement, as applicable. You should refer to the provisions of the indentures for provisions that may be important to you.

The terms and conditions described under this heading are terms and conditions that apply generally to the debt securities. The particular terms of any series of debt securities will be summarized in the applicable prospectus supplement. Those terms may differ from the terms summarized below.

Except as set forth in the indentures and described in the prospectus supplements, the indentures do not limit the amount of senior debt securities or subordinated debt securities we may issue under the indentures. In the event that our revolving credit facility with U.S. Bank, National Association, and Frost Bank is still in place, we would need to seek the approval of U.S. Bank and Frost Bank to issue any senior debt securities. We are not required to issue all of the debt securities of one series at the same time and, unless otherwise provided in an indenture and described in a prospectus supplement, we may, from time to time, issue additional debt securities under that series without the consent of the holders of the outstanding debt securities of that series. Additional

6

debt securities issued in this manner will have the same terms and conditions as the outstanding debt securities of that series, except for their original issue date and issue price, and will be consolidated with, and form a single series with, the previously outstanding debt securities of that series. In certain instances, additional debt securities of a series sold may be issued with a different CUSIP number from that assigned to previously issued debt securities of that issue.

We intend for the debt securities of each subordinated debt series to have such terms and conditions as will permit the subordinated debt securities that we issue and sell to investors to qualify as Tier 2 capital under the regulatory capital requirements for bank holding companies. As a result, the subordinated debt securities of each subordinated debt series will have a minimum term of five years, will be unsecured, will not have credit-sensitive features or other provisions that are inconsistent with safe and sound banking practice, and will have limited events of default and other provisions that will permit holders of the subordinated debt securities to accelerate payment of principal of, or interest on, any of the subordinated debt securities only upon the occurrence of any event other than our bankruptcy.

Terms and Conditions of Debt Securities to be Described in the Prospectus Supplement

The prospectus supplement relating to any debt securities of a series that we may offer will set forth the price or prices at which the debt securities will be offered to the public and the specific terms and conditions of the debt securities of that series to the extent such terms and conditions are not described in this prospectus. The prospectus supplement will set forth the aggregate principal amount of the debt securities of a series being offered by means of such prospectus supplement and the price(s) (expressed as a percentage of the principal amount) at which the debt securities will be offered and sold to the public. Each series of debt securities will be established and its terms and conditions set by a supplemental indenture. These terms and conditions of the debt securities may include, without limitation, the following:

7

Unless otherwise specified in the applicable prospectus supplement relating to the debt securities of a particular series, the debt securities will not be listed on any securities exchange.

We may offer and sell our debt securities at a substantial discount below their stated principal amount. The debt securities sold on that basis may be original issue discount, or OID, securities, which means that less than the entire principal amount of the original issue discount securities will be payable upon declaration of acceleration of their maturity. Special federal income tax, accounting and other considerations applicable to original issue discount securities will be described in the applicable prospectus supplement.

8

Any material federal income tax considerations applicable to any discounted debt securities or to debt securities issued at par that are treated as having been issued at a discount for federal income tax purposes are described in this prospectus and will be supplemented in the applicable prospectus supplement.

Special federal income tax, accounting and other considerations applicable to debt securities, the principal, premium, if any, or interest of which may be determined by reference to an index, formula or other method will be described in the applicable prospectus supplement.

Except as may be otherwise set forth in the prospectus supplement by which we offer particular debt securities, the indentures do not contain any provisions that would limit our ability to incur indebtedness, including indebtedness senior to the debt securities, or that would afford holders of debt securities protection in the event of a highly leveraged or similar transaction involving our Company. The indentures do not contain specific provisions that would afford debt securityholders protection in the event of a change of control, although such provisions may be included in the terms and conditions of the debt securities of a series by means of the supplemental indenture establishing that series. You should refer to the applicable prospectus supplement for information with respect to the deletion, modification or addition of any of the events of default or covenants that may be included in the debt securities of a series that are described below, including any addition of a covenant or other provision providing event risk or similar protection.

For purposes of the descriptions under the heading “Description of Debt Securities,” “subsidiary” means a corporation, a partnership, business or statutory trust, or a limited liability company a majority of the outstanding voting equity securities or a majority of the voting membership or partnership interests or beneficial interests in a trust, as the case may be (collectively, referred to as “voting equity securities”), of which is owned or controlled, directly or indirectly, by us or by one or more of our other subsidiaries. For the purposes of this definition, “voting equity securities” means securities having voting power for the election of directors, managers, managing partners or trustees, as the case may be, whether at all times or only so long as no senior class of stock has voting power by reason of any contingency.

Interest and Interest Rates

General

In the applicable prospectus supplement, we will designate the debt securities of a series as either bearing interest at a fixed rate of interest or bearing interest at a floating rate of interest. Each debt security will begin to accrue interest from the date it is originally issued. Interest on each such debt security will be payable in arrears on the interest payment dates set forth in the applicable prospectus supplement and as otherwise described below and at maturity or, if earlier, the redemption date described below. Interest will be payable to the holder of record of the debt securities at the close of business on the record date for each interest payment date, which record dates will be specified in such prospectus supplement. As used in the indentures, the term “business day” means any day, other than a Saturday or Sunday, that is neither a legal holiday nor a day on which banking institutions are generally authorized or required by law or regulation to close in Dallas, Texas.

Fixed Rate Debt Securities

If a series of debt securities being offered pursuant to this prospectus will bear interest at a fixed rate of interest, the debt securities of that series will bear interest at the annual interest rate specified on the cover page of the applicable prospectus supplement. Interest on those debt securities will be payable semi-annually in arrears on the interest payment dates for those debt securities or at such other intervals as are established in the terms of the debt securities of a particular series. If the maturity date, any redemption date or an interest payment date is not a business day, we will pay principal, premium, if any, and interest on the next business day, and no interest will accrue on, from and after the maturity date, the redemption date or that interest payment date. Interest on the fixed rate debt securities will be computed on the basis of a 360-day year of twelve 30-day months.

9

Floating Rate Debt Securities

If a series of debt securities being offered will bear interest at a floating rate of interest, the debt securities of that series will bear interest during each relevant interest period at the rate determined as set forth in the applicable prospectus supplement and as otherwise set forth below. Each floating rate debt security will have an interest rate basis or formula.

The floating rate debt securities may have a maximum or minimum rate limitation. In no event, however, will the rate of interest on the debt securities be higher than the maximum rate of interest permitted by Texas law as that law may be modified by United States law of general application.

The trustee or another bank or investment banking firm designated by us will act as the calculation agent for floating rate debt securities and, in that capacity, will compute the interest accruing on the debt securities unless otherwise specified in the applicable prospectus supplement.

If any interest payment date for the debt securities of a series bearing interest at a floating rate (other than the maturity date or a redemption date) would otherwise be a day that is not a business day, then the interest payment date will be postponed to the following date which is a business day, unless that business day falls in the next succeeding calendar month, in which case the interest payment date will be the immediately preceding business day. If the maturity date of such debt securities (or a tax or other redemption date, if earlier than the stated maturity date for those debt securities) falls on a day which is not a business day, then we will make the required payment of principal, premium, if any, and interest on the following day which is a business day, as if it were made on the date the payment was due. Interest will not accrue on, from or after the stated maturity date (or any tax or other redemption date) as a result of this delayed payment.

The calculation agent will reset the rate of interest on the debt securities of a series bearing interest at a floating rate on each interest payment date. If any of the interest reset dates for the debt securities is not a business day, that interest reset date will be postponed to the next succeeding business day, unless that day is in the next succeeding calendar month, in which case the interest reset date will be the immediately preceding business day. The interest rate set for the debt securities on a particular interest reset date will remain in effect during the interest period commencing on that interest reset date. Each interest period will be the period from and including the interest reset date to but excluding the next interest reset date or until the maturity date of the debt securities, as the case may be. The interest reset date relating to each interest period will be determined as set forth in the terms of each series of floating rate debt securities.

All percentages resulting from any calculation will be rounded to the nearest one hundred-thousandth of a percentage point, with five one-millionths of a percentage point rounded upward. Dollar amounts used in any calculation will be rounded to the nearest cent (with one-half cent being rounded upward).

The calculation agent will promptly notify the trustee of each determination of the interest rate, as well as of the interest period, the amount of interest expected to accrue for that interest period and the interest payment date related to each interest reset date, as soon as such information becomes available. The trustee will make such information available to the holders of the relevant debt securities upon request. The calculation agent’s determination of any interest rate and its calculation of the amount of interest for any interest period will be final and binding in the absence of a manifest error.

So long as floating rate debt securities of a series are outstanding, we will at all times maintain a calculation agent as to the debt securities of that series. We will appoint a bank, trust company, investment banking firm or other financial institution to act as the successor calculation agent to the trustee or any of its successors in that capacity in the event that:

10

Ranking

Senior Debt Securities

The senior debt securities of a series that we issue under the senior debt indenture will rank equally in right of payment of the principal of and premium, if any, and interest on such senior debt securities with all of our other unsecured and unsubordinated debt, including the senior debt securities of any other series.

Subordinated Debt Securities

As provided in the subordinated debt indenture and as described in the prospectus supplement describing the applicable series of subordinated debt securities, the payment of the principal of and premium, if any, and interest on the subordinated debt securities of any series, including amounts payable on any redemption or repurchase in accordance with the terms of such subordinated debt securities, will be subordinated to the extent and in the manner provided in the terms of the subordinated debt securities of a series in right of payment to the prior payment in full of all of our senior indebtedness, which is defined below. If there is a distribution to our creditors in a liquidation or winding up of our Company, or in a bankruptcy, reorganization, insolvency, receivership or similar proceeding relating to our Company, the holders of senior debt will first be entitled to receive payment in full of all amounts due on the senior debt (or provision shall be made for such payment in cash) before any payments may be made on the subordinated debt securities. Because of this subordination, holders of our senior debt securities and general creditors of our Company may recover more of the indebtedness of our Company owed to them, ratably, than will the holders of subordinated debt securities in the event of a distribution of assets upon bankruptcy, reorganization, insolvency, receivership or similar proceeding, or a liquidation, termination or winding up of our Company.

The supplemental indenture, board resolution or board resolution and related officers’ certificate establishing a series of subordinated debt securities will set forth the terms and conditions under which, if any, we will not be permitted to pay some or all of the principal of or premium, if any, or interest on the subordinated debt securities of a series upon the occurrence of an event of default or other circumstances arising under or with respect to senior indebtedness of our Company, including senior debt securities.

As discussed above, the indentures may place no limitation on the amount of indebtedness that we may incur, and the subordinated debt indenture will not limit the amount of debt senior to the subordinated debt securities of any series that we may incur. We expect to incur from time to time additional indebtedness constituting senior debt, which may include indebtedness that is senior to the subordinated debt securities but subordinate to our other obligations.

“Senior indebtedness” means the principal of, and premium, if any, and interest, including interest accruing after the commencement of any bankruptcy proceeding relating to our Company, on, or substantially similar payments we will make in respect of the following categories of indebtedness, whether that indebtedness was outstanding at the date of execution of the subordinated debt indenture or thereafter incurred, created or assumed:

11

However, “senior debt” excludes:

As used above, the term “purchase-money obligations” means indebtedness, obligations evidenced by a note, debenture, bond or other instrument, whether or not secured by a lien or other security interest issued to evidence the obligation to pay or a guarantee of the payment of, and any deferred obligation for the payment of, the purchase price of property but excluding indebtedness or obligations for which recourse is limited to the property purchased, issued or assumed as all or a part of the consideration for the acquisition of property or services, whether by purchase, merger, consolidation or otherwise, but does not include any trade accounts payable.

The applicable prospectus supplement and supplemental indenture may further describe the provisions, if any, applicable to the subordination of the subordinated debt securities of a particular series. The applicable prospectus supplement will describe as of a recent date the approximate amount of our senior debt outstanding as to which the subordinated debt securities of that series will be subordinated.

12

Structural Subordination

Because our Company is a holding company, our cash flows and consequent ability to service our obligations, including both our senior debt securities and subordinated debt securities, are dependent on dividends, distributions and other payments of earnings and other funds by our subsidiaries, particularly Independent Bank, to us. The payment of dividends and other distributions by our subsidiaries is contingent on their earnings and is subject to the requirements of federal banking regulations and other restrictions. For example, various banking laws applicable to Independent Bank limit the payment of dividends and other distributions by Independent Bank to us, and may, therefore, limit our ability to pay accrued interest owing on our outstanding senior debt securities and subordinated debt securities on any interest payment date or the principal of such senior debt securities and subordinated debt securities at their maturity. In addition, the debt securities will be structurally subordinated to all indebtedness and other liabilities of the our subsidiaries, because any right of our Company to receive any assets of its subsidiaries upon their liquidation or reorganization, and the consequent right of the holders of the debt securities to participate in those assets, will be effectively subordinated to the claims of that subsidiary’s secured and unsecured creditors. If our Company itself is recognized as a creditor of that subsidiary, our claims would still be subordinate to any security interest in the assets of that subsidiary and any indebtedness of that subsidiary senior to that held by our Company. Claims from creditors (other than us) on our subsidiaries may include long-term and medium-term debt and substantial obligations related to deposit liabilities, federal funds purchased, securities sold under repurchase agreements, other short-term borrowings and trade payables. Any capital loans that we make to Independent Bank would be subordinate in right of payment to deposits and to other indebtedness of Independent Bank.

Unsecured Obligations

Our senior debt securities and subordinated debt securities will be unsecured.

Conversion or Exchange of Debt Securities

The applicable prospectus supplement will describe the terms, if any, on which a series of debt securities may be converted into or exchanged for other of our securities. These terms will include whether conversion or exchange will be mandatory, at our option or at the option of the holder. We will also describe in the applicable prospectus supplement relating to any such convertible or exchangeable debt securities how we will calculate the amount or number of our other securities that holders of debt securities would receive if they were to convert or exchange their debt securities, the conversion price or exchange ratio and other terms related to conversion or exchange and any antidilution protections.

Redemption of Securities

We may redeem the debt securities, in whole or in part, at the prescribed redemption price, at the times and on the terms described in the applicable prospectus supplement. If we exercise that redemption option, we will notify the trustee and the registrar of the redemption date and of the principal amount of debt securities of the series to be redeemed.

Notice of redemption will be given to each holder of the debt securities to be redeemed at their addresses, as shown on the security register, at least 60 days prior to the date set for such redemption. The notice will set forth: the redemption date; the price at which the debt securities will be redeemed; if less than all of the outstanding debt securities of such series are to be redeemed, the identification (and, in the case of partial redemption, the respective principal amounts) of the particular debt securities to be redeemed; the place or places where such debt securities maturing after the redemption date are to be surrendered for payment of the price at which such debt securities will be redeemed; and the CUSIP number applicable to the debt securities to be redeemed.

At or prior to the opening of business on the redemption date, we will deposit or cause to be deposited with the trustee or with a paying agent (or, if we are acting as our own paying agent with respect to the debt securities

13

being redeemed, we will segregate and hold in trust as provided in the indenture) an amount of money sufficient to pay the aggregate redemption price of all of the debt securities or the part thereof to be redeemed on that date. On the redemption date, the price at which the debt securities will be redeemed will become due and payable upon all of the debt securities to be redeemed, and interest, if any, on the debt securities to be redeemed will cease to accrue on and after that date. Upon surrender of any such debt securities for redemption, we will pay those debt securities surrendered at the price set for such redemption.

If we elect to redeem debt securities, we will be required to notify the trustee of the aggregate principal amount of debt securities to be redeemed and the redemption date. If fewer than all the debt securities are to be redeemed, the trustee is required to select the debt securities to be redeemed proportionately, by lot or in a manner it deems fair and appropriate or as required by law. Any of the debt securities to be redeemed only in part must be surrendered at the office or agency established by us for such purpose, and we will execute, and the trustee will authenticate and deliver to you without service charge, new debt securities of the same series, containing identical terms and conditions, of any authorized denominations as requested by you, in an aggregate principal amount equal to and in exchange for the unredeemed portion of the debt securities you surrender.

Payment and Paying and Transfer Agent

We will make all payments of principal of and premium, if any, and interest on the debt securities of each series offered pursuant to this prospectus to the depository for the debt securities of that series, which will be The Depository Trust Company, or DTC, for so long as those debt securities remain in book-entry form. If certificated securities are issued as to the debt securities of any series, we will pay the principal of and the premium, if any, and interest on those debt securities by wire transfer in accordance with the instructions given to us by the holders of those debt securities. Except as otherwise noted below, all other payments with respect to certificated debt securities will be made at the office or agency of the paying agent within Dallas, Texas unless we elect to make interest payments by check mailed to the holders at their address set forth in the register of holders.

Under the terms of the indentures, we and the trustee will treat the registered holder of such debt securities (i.e., DTC (or its nominee)) as the owner thereof for all purposes, including the right to receive payments and for all other purposes. Consequently, neither we nor the trustee or any of our respective agents has or will have any responsibility or liability for:

We will maintain an office or agency in Dallas, Texas, where debt securities of each series may be presented for registration of transfer or for exchange and an office or agency where such debt securities may be presented and surrendered for payment. Wells Fargo Bank, National Association, the trustee under the indentures, will also be the registrar and paying agent for the debt securities of each series unless it resigns from such position or it is otherwise replaced in such capacities as provided in the applicable indentures. Holders will not have to pay any service charge for any registration of transfer or exchange of debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with such registration of transfer.

14

Same-Day Settlement

The debt securities will trade in the same-day funds settlement system in the United States until maturity. Purchases of debt securities in secondary market trading must be settled in immediately available funds. See “Book Entry Issuance.”

Denomination, Payment, Registration and Transfer

Unless otherwise specified in the applicable prospectus supplement, we will issue the debt securities of a series in denominations of $1,000 or integral multiples of $1,000.

Unless otherwise specified in the applicable prospectus supplement, we will pay the principal of, and applicable premium, if any, and interest on the debt securities of any series at the corporate trust office of the trustee, the address of which will be stated in the applicable prospectus supplement. At our option, we may pay interest by check mailed to the address of the person entitled to the interest payment as it appears in the register for the applicable debt securities or by wire transfer of funds to that person at an account maintained within the United States.

Any defaulted interest, which means interest not punctually paid or duly provided for on any interest payment date with respect to a debt security, will immediately cease to be payable to the registered holder on the applicable regular record date by virtue of his having been the registered holder on such date. We may pay defaulted interest either to the person in whose name the debt security is registered at the close of business on a special record date for the payment of the defaulted interest to be fixed by the trustee, notice of which is to be given to the holder of the debt security not less than ten days before the special record date, or at any time in any other lawful manner, all as more completely described in the indenture or supplemental indenture.

Subject to limitations imposed upon debt securities issued in book-entry form, the holder may exchange debt securities of any series for other debt securities of the same series and of a like aggregate principal amount and tenor but in different, authorized denominations upon surrender of the debt securities at the corporate trust office of the applicable trustee. In addition, subject to limitations imposed upon debt securities issued in book-entry form, the holder may surrender debt securities of any series for registration of transfer or exchange at the corporate trust office of the applicable trustee. Every debt security surrendered for registration of transfer or exchange must be duly endorsed or accompanied by a written instrument of transfer. No service charge will be imposed for any registration of transfer or exchange of any debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with any registration of transfer or exchange of any debt securities. If the applicable prospectus supplement refers to any transfer agent in addition to the applicable trustee, which additional transfer agent is initially designated by us with respect to any series of debt securities, we may at any time rescind the designation of that transfer agent or approve a change in the location through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for that series of debt securities. We may at any time designate additional transfer agents with respect to any series of debt securities.

If we redeem the debt securities of any series, neither we nor any trustee will be required to:

15

Global Securities

We may issue the debt securities of a series in whole or in part in the form of one or more global securities to be deposited with, or on behalf of, a depository or with a nominee for a depository identified in the applicable prospectus supplement relating to that series. We will issue global securities in registered form and in either temporary or permanent form. The specific terms of the depository arrangement with respect to a series of debt securities will be described in the prospectus supplement relating to that series.

Our obligations with respect to the debt securities of any series, as well as the obligations of the applicable trustee with respect to the debt securities of such series, run only to persons who are registered holders of debt securities. For example, once we make payment to the registered holder, we have no further responsibility for that payment even if the recipient is legally required to pass the payment along to an individual investor but fails to do so. As an indirect holder, an investor’s rights relating to a global security will be governed by the account rules of the investor’s financial institution and of the depositary and/or participant of the depositary, as well as general laws relating to transfers of debt securities.

An investor should be aware that when debt securities are issued in the form of global securities:

The prospectus supplement for a series of debt securities will list the special situations, if any, in which a global security will be exchanged for physical certificates representing debt securities represented by the global securities. After that exchange, the investor may choose whether to hold debt securities directly or indirectly through an account at the investor’s bank or brokerage firm. In that event, investors must consult their banks or brokers to find out how to have their interests in debt securities transferred to their own names so that they may become direct holders. When a global security is exchanged for physical certificates, the depositary, and not us or one of the trustees, is responsible for deciding the names of the institutions that will be the initial direct holders of the debt securities represented by the global security.

Merger, Consolidation or Sale of Assets

We will not be permitted to consolidate with or merge into any other entity, or sell, lease, transfer or convey all or substantially all of our properties and assets, either in one transaction or a series of transactions, to any other entity and no other entity will consolidate with or merge into us, or sell, lease, transfer or convey all or substantially all of its properties and assets to us unless:

(1) either:

16

(2) immediately after giving effect to the transaction and treating any indebtedness that becomes our obligation as a result of that transaction as having been incurred by us at the time of the transaction, no event of default under the applicable indenture, and no event which, after notice, the lapse of time or both, would become an event of default will have occurred and be continuing.

The conditions described in (1) and (2) above would not apply to the direct or indirect transfer of the stock, assets or liabilities of any of our subsidiaries to another of our direct or indirect subsidiaries.

Except as provided in this prospectus or as may otherwise be provided in the applicable prospectus supplement, the indenture and the terms of the debt securities will not contain any event risk or similar covenants that are intended to afford protection to holders of any debt securities in the event of a merger, a highly leveraged transaction or other significant corporate event involving us or our subsidiaries, whether or not resulting in a change of control, which may adversely affect holders of the debt securities.

Additional Covenants and/or Modifications to the Covenant Described Above

Any covenants of our Company in addition to, and/or modifications to, the covenant relating to mergers, consolidations and sales of assets described above with respect to any series of debt securities, including any covenants relating to limitations on incurrence of indebtedness or incurrence of liens or any affirmative covenants, other negative covenants or financial covenants, will be set forth in the indenture and described in the prospectus supplement relating to that series of debt securities.

Unless the applicable prospectus supplement indicates otherwise, the indentures do not contain a restrictive covenant on the incurrence of debt of the type described above, nor do they contain any other provision which restricts us from, among other things:

Events of Default; Right to Accelerate

Senior Debt Securities. Under the senior debt indenture, but subject to any modifications or deletions provided in any supplemental indenture, a board resolution, or a board resolution and related officers’ certificate with respect to or establishing the terms and conditions of the senior debt securities of any specific series, an event of default will occur with respect to the senior debt securities upon the occurrence of any of the following events:

17

If any bankruptcy or insolvency-related event of default described above occurs, the principal amount and interest on the senior debt securities will become immediately due and payable, subject to the broad equity powers of a federal bankruptcy court and the determination by that court of the nature and status of the payment claims of the holders of the senior debt securities. If any other event of default described above or established as a term of the senior debt securities of a series occurs and is continuing, the senior debt trustee or the holders of 25% of the aggregate principal amount of the outstanding senior debt securities of that series may accelerate the maturity of the outstanding senior debt securities of that series and declare the principal of and accrued and unpaid interest on such senior debt securities to be immediately due and payable. Upon such a declaration, the principal of (or such lesser amount as may be provided for in the terms of the senior debt securities of that series) and all accrued and unpaid interest on such senior debt securities will become immediately due and payable upon notice of such declaration being given in writing to the Company and, if the acceleration is by the holders, the senior debt trustee. At any time after a declaration of acceleration with respect to the senior debt securities of a series has been made, but before a judgment or decree for payment of the money due has been obtained, the holders of a majority in principal amount of outstanding senior debt securities of that series may rescind and annul the consequences of the event of default, but only if certain conditions have been satisfied.

Subordinated Debt Securities. Under the subordinated debt indenture, but subject to any modifications or deletions provided in any supplemental indenture, a board resolution, or a board resolution and related officers’ certificate with respect to any specific series of subordinated debt securities, an event of default will occur with respect to the subordinated debt securities upon the occurrence of any of the following events:

18

If an event of default based on the entry of a decree or order for relief in a bankruptcy or insolvency proceeding or the commencement by us of a bankruptcy or insolvency proceeding or our consent to the entry of an order in an involuntary bankruptcy or insolvency proceeding that adjudicates us as being insolvent occurs, the principal amount and interest on the subordinated debt securities shall become immediately due and payable, subject to the broad equity powers of a federal bankruptcy court and the determination by that court of the nature and status of the payment claims of the holders of the subordinated debt securities. Unless the terms of the subordinated debt securities of a series provide otherwise, if any non-insolvency event of default described above or established as a term of the subordinated debt securities of a series occurs and is continuing, the subordinated debt trustee or the holders of 25% of the aggregate principal amount of the outstanding subordinated debt securities of that series may accelerate the maturity of the outstanding subordinated debt securities of that series and declare the principal of and accrued and unpaid interest on such subordinated debt securities to be immediately due and payable. Upon such a declaration, the principal of (or such lesser amount as may be provided for in the terms of the senior debt securities of that series) and all accrued and unpaid interest on such subordinated debt securities will become immediately due and payable upon notice of such declaration being given in writing to our Company and, if the acceleration is by the holders, the subordinated debt trustee. At any time after a declaration of acceleration with respect to the subordinated debt securities of a series has been made, but before a judgment or decree for payment of the money due has been obtained, the holders of a majority in principal amount of outstanding subordinated debt securities of that series may rescind and annul the consequences of the event of default, but only if certain conditions have been satisfied.

We may offer subordinated debt securities of a series that we intend to qualify as “Tier 2 capital” under the federal regulatory rules and guidelines for bank holding company capital. For such subordinated debt securities to so qualify as “Tier 2 capital,” the maturity of such subordinated debt securities may not be accelerated upon the occurrence and continuation of an event of default unless the event of default is one based on the entry of a decree or order for relief in a bankruptcy or insolvency proceeding or the commencement by us of a bankruptcy or insolvency proceeding or our consent to the entry of an order in an involuntary bankruptcy or insolvency proceeding as discussed above. Notwithstanding the discussion appearing above of the rights of the subordinated debt trustee or holders of subordinated debt securities to accelerate the maturity of such subordinated debt securities upon the occurrence of a non-insolvency event of default, the terms of the subordinated debt securities of a series intended to qualify as “Tier 2 capital” will expressly limit the rights of the subordinated debt trustee and the holders of the subordinated debt securities of such series to declare an acceleration of the maturity of such subordinated debt securities upon the occurrence of a non-insolvency default and such limitation will be described in any prospectus supplement by which we offer subordinated debt securities of that series for sale. As a consequence of that limitation, with respect to our subordinated debt securities of a series intended to qualify as “Tier 2 capital,” neither the trustee nor the holders of the subordinated debt securities of any series or any group of holders of any portion of the outstanding subordinated debt securities of one or

19

more series will have the right to accelerate the subordinated debt securities of any series in the event of a default in the payment of principal of, or premium, if any, or interest on, the subordinated debt securities of that series or as a result of our nonperformance of any other covenant applicable to or obligation arising under the terms of the subordinated debt securities of that series or the subordinated debt indenture. If we default in our obligation to pay any interest on the subordinated debt securities when due and payable and such default continues for a period of 30 days, or if we default in our obligation to pay the principal amount due upon maturity, or if we breach any covenant or agreement contained in the subordinated debt indenture and that default continues for any grace period, then the subordinated debt trustee may, subject to certain limitations and conditions, seek to enforce its rights and the rights of the holders of subordinated debt securities of the performance of any covenant or agreement in the indenture. As a result of such limitations on the rights and remedies of the holders of subordinated debt securities of a series intended to qualify as “Tier 2 capital”, the holders of our senior debt securities, holders of our other senior indebtedness, holders of our subordinated debt securities of a series not intended to qualify as “Tier 2 capital” and our general creditors would be able to act to recover amounts owing to them prior to the holders of our subordinated debt securities.

Collection of Indebtedness