Washington Rent Stabilization 2026 (HB 1217): The 9.683% Cap Explained

Washington Rent Stabilization 2026 (HB 1217): The 9.683% Cap Explained

Washington now has statewide rent stabilization. Under HB 1217, there is a ceiling on how much you can raise rent, a formula that sets that ceiling each year, a hard rule against increases in the first year of a tenancy, and a notice requirement that is longer than most operators are used to. This 2026 guide gives Washington landlords and property managers the practical framework — anchored to the stable structure of the law, with a reminder to confirm the annual figure that changes year to year.

The law and agency to build around

For Washington, anchor every rent-increase decision to HB 1217 and the body that administers it, the Washington State Department of Commerce. Multi-state operators get into trouble by carrying a rent-increase habit from an uncapped state into Washington — a percentage or a notice period that was fine elsewhere can now be an over-cap increase or a defective notice here.

The first operating rule is to put the state name at the top of every increase checklist. The second is to separate the business decision (how much you'd like to raise) from the legal ceiling (how much HB 1217 lets you).

The 2026 cap: 9.683%

For the period January 1 through December 31, 2026, the annual rent-increase cap is 9.683%. This figure is set annually, so it is not a permanent number — confirm the current-year figure with the Department of Commerce before sending any increase. Hard-coding 9.683% into a workflow that outlives 2026 is exactly the kind of mistake that produces an over-cap notice.

The formula behind the cap

The cap is not an arbitrary percentage — it comes from a formula. After the first 12 months of a tenancy, rent increases are limited to 7% plus CPI, or 10%, whichever is less. In other words, the ceiling floats with inflation but is hard-capped at 10% no matter how high CPI runs. The published annual figure (9.683% for 2026) is the result of running that formula for the year. Knowing the formula matters because it tells you the number can move within a known band each year, and it will never exceed the 10% hard cap.

The first-year rule: no increase in the first 12 months

HB 1217 prohibits any rent increase during the first 12 months of a tenancy. This is a bright-line rule, separate from the percentage cap: it does not matter how small the increase is, you cannot raise rent at all inside that first year. Calendar the 12-month anchor from the tenancy start date so no increase can be scheduled before it.

The 90-day notice requirement

Rent increases under HB 1217 require 90 days' written notice. For operators used to 30- or 60-day notice, this is the change most likely to trip up a routine increase: a notice served on the old timeline is defective, and you have to restart the clock. Build the 90-day lead time into your increase workflow so the notice always goes out early enough to be valid.

Common mistakes

Avoid raising rent above the current-year cap, using last year's percentage instead of confirming this year's figure, raising rent at all during the first 12 months of a tenancy, serving less than 90 days' notice, or assuming Washington works like an uncapped state. Each of these can turn a routine increase into a defective — and unenforceable — one.

Managing this in software

Your system should cap the proposed increase at the current-year HB 1217 figure, block any increase scheduled inside the first 12 months of a tenancy, enforce a minimum 90-day notice lead time on every increase notice, and flag the cap figure for annual re-verification against the Department of Commerce so it never runs on a stale number. Treat a rent increase as a compliance check, not just a billing change.

How Proprietio helps

Proprietio's compliance engine tracks these state rules and flags what changed, so your leases, notices, and rent increases stay current as the law moves — without you watching every bill. See how on your portfolio — free rental audit.

Sources

• Washington State Department of Commerce — HB 1217 Landlord Resource Center. Confirm the current-year cap figure, the formula inputs, and the notice timeline on the official Commerce pages before acting.

⚠️ This is general information, not legal advice. Landlord-tenant law is state-specific and changes often — verify the current rule with your state agency or a local attorney before acting.