Washington Revised Code Title 49. Labor Regulations § 49.48.200. Overpayment of wages--Government employees

(1) Debts due the state or a county or city for the overpayment of wages to their respective employees may be recovered by the employer by deductions from subsequent wage payments as provided in RCW 49.48.210, or by civil action. If the overpayment is recovered by deduction from the employee's subsequent wages, each deduction shall not exceed: (a) Five percent of the employee's disposable earnings in a pay period other than the final pay period; or (b) the amount still outstanding from the employee's disposable earnings in the final pay period. The deductions from wages shall continue until the overpayment is fully recouped.

(2) Nothing in this section or RCW 49.48.210 or 49.48.220 prevents: (a) An employee from making payments in excess of the amount specified in subsection (1)(a) of this section to an employer; or (b) an employer and employee from agreeing to a different overpayment amount than that specified in the notice in RCW 49.48.210(1) or to a method other than a deduction from wages for repayment of the overpayment amount.