Washington Revised Code Title 59. Landlord and Tenant § 59.20.150. Service of notice on landlord or tenant

(1) Any notice required by this chapter to be given to a tenant shall be served on behalf of the landlord: (a) By delivering a copy personally to the tenant; or (b) if the tenant is absent from the mobile home, manufactured home, or park model by affixing a copy of the notice in a conspicuous place on the mobile home, manufactured home, or park model and also sending a copy through the mail addressed to the tenant at the tenant's last known address.

(2) Any notice required by this chapter to be given to the landlord shall be served by the tenant in the same manner as provided for in subsection (1) of this section, or by mail to the landlord at such place as shall be expressly provided in the rental agreement.

(3) The landlord shall state in any notice of eviction required by RCW 59.20.080(1) as now or hereafter amended the specific reason for eviction in a clear and concise manner.