Wash. Rev. Code § 41.48.170
The office of financial management shall direct the state treasurer to, and the state treasurer shall, periodically transfer to the sick leave account in the general fund moneys sufficient to reimburse the sick leave account for payments on account of sickness. State agencies shall place in allotment reserve status and cause to be lapsed at the end of the biennium an amount equal to the sick leave pay and the employer's share of all federal old age and survivor's insurance payments rendered unnecessary by reason of RCW 41.48.120. When directing state agencies to place funds in reserve status, the office of financial management shall promulgate allotment instructions which conserve, to the fullest extent possible, state general fund appropriations.
RCW 41.48.170