AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON MARCH 2, 2006
                                                      REGISTRATION NO. 333-64924
--------------------------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                 ---------------


                         POST EFFECTIVE AMENDMENT NO. 1
                                       TO
                                    FORM S-8
             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
                                 ---------------

                              GLACIER BANCORP, INC.
             (Exact name of registrant as specified in its charter)



            MONTANA                                     81-0519541
(State or other jurisdiction of             (I.R.S. employer identification no.)
 incorporation or organization)


          49 COMMONS LOOP, KALISPELL, MONTANA 59903-0027 (406) 756-4200
 (Address, including zip code, and telephone number, including area code, of
                   registrant's principal executive offices)

                                   ----------

   AMENDED AND RESTATED GLACIER BANCORP, INC. 1995 EMPLOYEE STOCK OPTION PLAN
                              (Full title of plan)

                                   -----------

                          Copies of communications to:
STEPHEN M. KLEIN, ESQ.                             MICHAEL J. BLODNICK
Graham & Dunn PC                                   P. O. Box 27
Pier 70, 2801 Alaskan Way, Suite 300               49 Commons Loop
Seattle, Washington 98121-1128                     Kalispell, Montana 59903-0027
(206) 340-9648                                     (406) 756-4200


                              EXPLANATORY STATEMENT

This post-effective amendment to the registration statement on Form S-8
(Registration No. 333-64924) (the "Registration Statement") is being filed by
Glacier Bancorp, Inc. (the "Registrant" or "Glacier") to deregister 1,046,994
shares of its common stock (as adjusted for subsequent stock splits and stock
dividends) previously registered under the Registration Statement with respect
to shares reserved for issuance under the Registrant's Amended and Restated
Glacier Bancorp, Inc. 1995 Employee Stock Option Plan (the "1995 Plan"). Under
the Registration Statement, an aggregate of 4,022,584 shares (as adjusted for
subsequent stock splits and stock dividends) were registered for issuance under
the 1995 Plan. As of this date, 1,200,121 shares remain subject to granted but
unexercised options under the 1995 Plan.

At the 2005 Annual Shareholder Meeting, shareholders approved the 2005 Stock
Incentive Plan (the "2005 Plan"). The 2005 Plan supercedes the 1995 Plan and as
a result, Registrant has terminated all further offerings of its common stock
under the 1995 Plan and pursuant to the Registration Statement. On May 15, 2005,
the Registrant filed a registration statement on Form S-8 (Registration No.
333-125024) to register 2,500,000 shares of its common stock for issuance under
the 2005 Plan.

In accordance with an undertaking made by Glacier in the Registration Statement
to remove from registration, by means of a post-effective amendment, any shares
of the Registrant's common stock which remain unsold at the termination of the
offering, the Registrant removes from registration all shares of Glacier common
stock registered under the Registration Statement which remain unsold as of the
Effective Time.

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                                   SIGNATURES

     Pursuant to the requirements of the Securities Act, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Post Effective Amendment No. 1 to Form S-8 and has
duly caused this Registration Statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of Kalispell, State of
Montana, on the 22nd day of February 2006.

                                                   GLACIER BANCORP, INC.


                                                   By    /s/ Michael J. Blodnick
                                                   -----------------------------
                                                   Michael J. Blodnick
                                                   President and Chief Executive
                                                   Officer

     Pursuant to the requirements of the Securities Act, this Registration
Statement has been signed by the following persons in the capacities indicated,
on the 22nd day of February 2006.


     Signature                              Title



                              
  /s/ Michael J. Blodnick        President, Chief Executive Officer and Director
---------------------------
Michael J. Blodnick              (Principal Executive Officer)


   /s/ James H. Strosahl         Executive Vice President and CFO
---------------------------
James H. Strosahl                (Principal Financial and Accounting Officer)


   /s/ Everit A. Sliter          Chairman of the Board
---------------------------
Everit A. Sliter


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         William L. Bouchee *                             Director
--------------------------------------------
William L. Bouchee

         /s/ Allen J. Fetscher                            Director
--------------------------------------------
Allen J. Fetscher

         Fred J. Flanders *                               Director
--------------------------------------------
Fred J. Flanders

         /s/ Jon W. Hippler                               Director
--------------------------------------------
Jon W. Hippler

         /s/ L. Peter Larson                              Director
--------------------------------------------
L. Peter Larson

         John S. MacMillan *                              Director
--------------------------------------------
John S. MacMillan


         /s/ Michael J. Blodnick
------------------------------------
Michael J. Blodnick, Attorney  --in-Fact *



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