Washington rent increase notice calculator.
Enter the current rent, new rent, and effective date. Get the required notice period, rent-cap compliance check, and whether your effective date is legal. Built from RCW 59.18.140 (90-day advance notice for any rent increase, HB 1217) and RCW 59.18.700 series.
Generate the Washington rent increase notice, signature-ready, $29.
The calculator above gave you the notice period. The template below puts it on a Washington-specific notice with the statutory wording, your tenant's name, the new rent, and the effective date filled in. Audited line by line against RCW 59.18.140 (90-day advance notice for any rent increase, HB 1217).
Get the Washingtonrent increase template, $29 →The statutes behind this calculator.
Washington HB 1217 (2024) requires 90 days advance notice for any rent increase, prohibits any increase during the first 12 months, and caps annual increases at the lower of CPI + 7% or 10% flat. Buildings under 12 years old are exempt. The rent cap framework sunsets July 1, 2040.
- ·Washington prohibits any rent increase during the first 12 months of a tenancy
- ·After 12 months, increase must not exceed the lower of CPI + 7% or 10% flat
- ·12-year CO exemption is rolling; a 2015 building becomes covered in 2027
- ·HB 1217 sunsets July 1, 2040 unless extended
- ·Buildings with certificate of occupancy issued within the last 12 years (rolling exemption)
What this calculator is, and what it is not.
This calculator applies the Washington rules as of early 2026. It is not legal advice. Housing law changes year to year and local ordinances (especially in rent-controlled cities) can apply stricter rules. For contested cases, consult a Washington-licensed attorney.
Source: https://leasekit.io/washington-rent-increase-calculator. Built by a small team of legal researchers and developers.