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                                                                    EXHIBIT 10.6



                                VOTING AGREEMENT

Frontier Financial Corporation
332 SW Everett Mall Way
Everett, Washington 98204

Gentlemen:

        In order to induce you to enter into an Agreement and Plan of Mergers
(the "Merger Agreement") dated of even date herewith by and among Frontier
Financial Corporation ("Frontier") and Valley Bancorporation. ("Valley"), the
undersigned, for himself, his heirs and legal representatives, hereby agrees,
represents, warrants and covenants with and to Frontier as follows:

        1. The undersigned beneficially owns the shares of common stock of
Valley ("Valley Common Stock") set forth beneath the undersigned's name below
and no other shares of Valley Common Stock. Such shares are so owned free and
clear of any lien, right or encumbrance whatsoever, except for any pledge of
such shares to secure a loan to the undersigned, and no proxy has been granted
with respect thereto and the undersigned has full capacity, power and authority
to vote such shares without the consent or approval of any other party in the
absence of a default under any such loan secured by such shares. If any of such
shares are currently pledged to secure a loan to the undersigned, the
undersigned (i) represents and warrants that such loan is not in default and no
event or condition exists that with notice, lapse of time or both would
constitute such a default, and (ii) agrees to take all such action as may be
necessary to prevent any such default, event or condition to exist in order to
prevent the lender from taking title to such shares and to continue to enable
the undersigned to vote such shares as hereinafter set forth.

        2. The undersigned hereby agrees to vote such shares in favor of
approval of the Merger Agreement and, as a shareholder, agrees to take all
necessary action to consummate the Mergers (as defined in the Merger Agreement)
as expeditiously as possible.

        3. The undersigned covenants that until the earlier of the consummation
of the Mergers or the termination of the Merger Agreement, the undersigned will
not sell, permit a lien or other encumbrance to exist with respect to (except as
hereinabove provided), or grant any proxy in respect of (except as hereinabove
provided and for proxies solicited by the Board of Directors of Valley in
connection with the special meeting to vote on the approval of the Merger
Agreement or in connection with any annual meeting of shareholders), the shares
of Valley Common Stock set forth below, unless all the other parties to any such
sale or other transaction enter into an agreement in form and substance
satisfactory to Frontier embodying the benefits and rights contained herein.

        4. The undersigned covenants that the undersigned will not, without the
prior written consent of Frontier and Valley: (i) make any public announcement
with respect to the Mergers; (ii) submit or seek any other person or entity to
submit a proposal for a tender offer, merger or similar transaction with Valley;
or (iii) vote the shares owned or controlled by the undersigned in favor of,
solicit proxies or seek another person or entity to solicit proxies on behalf
of, a proposal, the purpose of which is to oppose or nullify the Mergers.


                                            Very truly yours,


                                            ___________________________________
                                            (First Name)  (Last Name)

NUMBER OF SHARES:_________                  Dated:  July ____, 1998