Wash. Rev. Code § 35.58.160
The chair and committee chairs of the metropolitan council except elected public officials serving on a full-time salaried basis may receive such compensation as the other members of the metropolitan council shall provide. Members of the council other than the chair and committee chairs shall receive compensation of fifty dollars per day or portion thereof for attendance at metropolitan council or committee meetings, or for performing other services on behalf of the metropolitan municipal corporation, but not exceeding a total of four thousand eight hundred dollars in any year, in addition to any compensation which they may receive as officers of component cities or counties: PROVIDED, That elected public officers serving in such capacities on a full-time basis shall not receive compensation for attendance at metropolitan, council, or committee meetings, or otherwise performing services on behalf of the metropolitan municipal corporation: PROVIDED FURTHER, That committee chairs shall not receive compensation in any one year greater than one-third of the compensation authorized for the county commissioners or county councilmembers of the central county.
Any member of the council may waive all or any portion of his or her compensation payable under this section as to any month or months during his or her term of office, by a written waiver filed with the council as provided in this section. The waiver, to be effective, must be filed any time after the member's selection and prior to the date on which the compensation would otherwise be paid. The waiver shall specify the month or period of months for which it is made.
All members of the council shall be reimbursed for expenses actually incurred by them in the conduct of official business for the metropolitan municipal corporation.
RCW 35.58.160