RCW 4.16.280: New promise must be in writing.

No acknowledgment or promise shall be sufficient evidence of a new or continuing contract whereby to take the case out of the operation of this chapter, unless it is contained in some writing signed by the party to be charged thereby; except, an acknowledgment or promise made after the limitation period has expired shall not restart, revive, or extend the limitation period. This section shall not alter the effect of any payment of principal or interest.