210 , leases over 12 months must be notarized in order to be valid. If the dwelling is rented before the end of the 30 days, the former tenant must pay only until the new tenant begins paying rent.The law requires that month-to-month tenants give landlords at least 20 days written notice before vacating their units. This guide covers most people who pay rent for the place where they live (called residential tenants) in Washington State. Standard Lease Agreement (City of Seattle version) – The most popular rental contract with a start and end date and rent that is due on the first of each month. In WA state, apartment rental leases longer than 12 months are not valid unless notarized. Can I break my lease after the 12-month mark? You and the owner can negotiate any legal terms to the lease, including the length (legally, leases for a residence are limited to just a few years) Residential Rental Forms. Rent is typically due on the first day of each month in Washington, unless specified otherwise in the rental agreement.