Wash. Rev. Code § 35A.12.070
The salaries of the mayor and the councilmembers shall be fixed by ordinance and may be revised from time to time by ordinance, but any increase in the compensation attaching to an office shall not be applicable to the term then being served by the incumbent if such incumbent is a member of the city legislative body fixing his or her own compensation or as mayor in a mayor-council code city casts a tie-breaking vote relating to such ordinance: PROVIDED, That if the mayor of such a city does not cast such a vote, his or her salary may be increased during his or her term of office.
Until the first elective officers under this mayor-council plan of government may lawfully be paid the compensation provided by such salary ordinance, such officers shall be entitled to be compensated in the same manner and in the same amount as the compensation paid to officers of such city performing comparable services immediately prior to adoption of this mayor-council plan.
Until a salary ordinance can be passed and become effective as to elective officers of a newly incorporated code city, such first officers shall be entitled to compensation as follows: In cities having less than five thousand inhabitants, the mayor shall be entitled to a salary of one hundred and fifty dollars per calendar month and a councilmember shall be entitled to twenty dollars per meeting for not more than two meetings per month; in cities having more than five thousand but less than fifteen thousand inhabitants, the mayor shall be entitled to a salary of three hundred and fifty dollars per calendar month and a councilmember shall be entitled to one hundred and fifty dollars per calendar month; in cities having more than fifteen thousand inhabitants, the mayor shall be entitled to a salary of twelve hundred and fifty dollars per calendar month and a councilmember shall be entitled to four hundred dollars per calendar month: PROVIDED, That such interim compensation shall remain in effect only until a salary ordinance is passed and becomes effective as to such officers, and the amounts herein provided shall not be construed as fixing the usual salary of such officers. The mayor and councilmembers shall receive reimbursement for their actual and necessary expenses incurred in the performance of the duties of their office, or the council by ordinance may provide for a per diem allowance. Procedure for approval of claims for expenses shall be as provided by ordinance.
RCW 35A.12.070
Limitations on salaries: State Constitution Art. 11 s 8.