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                                                                       Exhibit 5

             CHRISTENSEN, MOORE, COCKRELL, CUMMINGS & AXELBERG, P.C.

DANA L. CHRISTENSEN                                        TWO MEDICINE BUILDING
MIKEL L. MOORE                                       160 HERITAGE WAY, SUITE 104
    [ALSO ADMITTED IN ARIZONA]                               KALISPELL, MT 59901
DALE R. COCKRELL
    [ALSO ADMITTED IN SOUTH DAKOTA
    AND COLORADO]                                                  P.O. BOX 7370
STEVEN E. CUMMINGS                                      KALISPELL, MT 59904-0370
TRACY AXELBERG                                            OFFICE: (406) 751-6000
SEAN P. GOICOECHEA                                           FAX: (406) 756-6522

                                  May 11, 2006

The Board of Directors
Glacier Bancorp, Inc.
49 Commons Loop
Kalispell, Montana 59901

      RE: LEGAL OPINION REGARDING VALIDITY OF SECURITIES OFFERED

Ladies and Gentlemen:

      We have acted as special counsel for Glacier Bancorp, Inc., a corporation
("Glacier"), in connection with the registration under the Securities Act of
1933, as amended (the "Act") of up to 1,300,000 shares of Glacier common stock,
$0.01 par value per share (the "Shares"), to be issued in accordance with the
Plan and Agreement of Merger dated as of April 20, 2006 (the "Plan") between
Glacier and Citizens Development Company.

      In connection with the Shares that will be issued under the Plan, we have
examined the following: (i) the Plan; (ii) the Registration Statement on Form
S-4 to be filed by Glacier with the Securities and Exchange Commission (the
"Registration Statement"); and (iii) such other documents as we have deemed
necessary to form the opinion expressed below. As to various questions of fact
material to such opinion, where relevant facts were not independently
established, we have relied upon statements of officers of Glacier or
representations and warranties of Glacier contained in the Plan. We have assumed
without independent investigation or review, the accuracy and completeness of
the facts and representations and warranties contained in the documents listed
above or otherwise made known to us.

      Our opinion assumes that the Shares are issued in accordance with the
terms of the Plan after the Registration Statement has become effective under
the Act.

      Based upon and relying solely upon the foregoing, we advise you that in
our opinion, the Shares, or any portion thereof, when issued pursuant to the
Plan, after the Registration Statement has become effective under the Act, will
be validly issued under the laws of the State of Montana and will be fully paid
and nonassessable.

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Glacier Bancorp, Inc.
May 11, 2006
Page 2

      This opinion letter is limited to the application of the laws of the State
of Montana and the federal laws of the United States of America, and we express
no opinion as to the laws of any other jurisdictions.

      We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the legal reference to this firm under the caption
"Certain Legal Matters" as having passed upon the validity of the Shares. In
giving such consent, we do not thereby admit that we are experts within the
meaning of the Act.

                                    Very truly yours,

                                    CHRISTENSEN, MOORE, COCKRELL, CUMMINNGS
                                    & AXELBERG, P.C.

                                    /s/ Christensen, Moore, Cockrell, Cummings &
                                        Axelberg, P.C.
