Last updated: June 11, 2026
Washington's legislature revisits landlord-tenant law nearly every session, and 2026 was no exception. Four changes affect how you serve notices and what your lease has to say, and they alone landed with three different effective dates: two took effect June 11, 2026, and two more arrive at the end of the year. Here is what changed, when each one applies, and what you need to do.
This is a plain-English summary, not legal advice. Confirm the specifics with your attorney or property manager before you change your forms.
At a glance
| Change | Bill | Effective | Lease update needed? |
|---|---|---|---|
| Regular mail for notices | HB 2664 | June 11, 2026 | No, update service process |
| Portable cooling devices | ESSB 6200 | June 11, 2026 | Only if you restrict window units |
| Flood risk disclosure | SB 6237 | Leases after Dec 31, 2026 | Yes |
| Smart access privacy | ESSB 5937 | Jan 1, 2027 | Mainly multi-unit buildings |
1. Regular mail is back for eviction and rent increase notices (June 11, 2026)
As of June 11, 2026, Washington landlords can again serve eviction and rent increase notices by ordinary first-class mail instead of certified mail. The change comes from House Bill 2664 (Chapter 144, Laws of 2026), which passed the House unanimously and was signed into law.
It corrects a 2025 law (HB 1003) that had required certified mail for substitute service and posting-and-mailing. That rule created a delivery problem: when tenants weren't home to sign, notices were held at the post office and came back undelivered. The Washington Multi-Family Housing Association, the landlord group that pushed for the fix, reported that more than 60% of mailed notices were being returned. Going back to first-class mail is meant to get notices into tenants' hands again.
What does not change: the rest of the service process under RCW 59.12.040 still applies. You start by attempting personal delivery. If that fails, you post the notice conspicuously on the door and mail a copy the same day. Get the steps wrong and a court can dismiss the unlawful detainer, sending you back to the start. The 14-day pay-or-vacate notice is still the required notice for nonpayment of rent, and Seattle's just-cause ordinance and local disclosure requirements still apply on top of state law.
What you need to do: update your service templates and stop paying for certified mail you no longer need. Notices served before June 11, 2026 followed the old certified-mail process, so there's nothing to redo; the new rule applies to notices served on or after that date.
2. Tenants get the right to install portable cooling devices (June 11, 2026)
As of June 11, 2026, Washington landlords generally cannot stop a tenant from installing a portable cooling device of their choosing. This comes from Engrossed Substitute Senate Bill 6200 (Chapter 184, Laws of 2026), signed March 24, 2026, and added to the Residential Landlord-Tenant Act. The law defines a portable cooling device as an air conditioner or portable heat pump, including window-mounted and floor-standing units.
You are not required to install AC. You just can't prohibit the tenant from doing it themselves, and you can't charge a fee for the use or installation of one.
You keep some control over window-mounted units specifically. You can restrict or prohibit a window-mounted device if the window is a required emergency exit and the unit blocks it, if it stops the tenant from locking a window reachable from outside, if installation needs hardware that would damage the window or puncture the exterior wall, if the unit can't be secured against falling, or if your insurance policy prohibits window units. That last one only counts if the restriction is written into the lease and you give the tenant written proof of the insurance restriction. For any device, you can require that it drain properly to avoid water damage and that it be available for inspection or servicing. Whether you can restrict a given unit comes down to the specific window, your insurance policy, and your lease language, so the answer can vary from property to property.
If you restrict or prohibit window-mounted cooling devices, you have to spell out the tenant's rights, responsibilities, and any restrictions in the lease itself. Silence isn't an option if you want to enforce a restriction.
What you need to do: decide whether you're restricting window units at any of your properties. The rule is already in effect, so if you are, get the disclosure language into your lease right away.
3. New flood risk disclosure for leases signed after December 31, 2026
Any residential lease a Washington landlord signs after December 31, 2026 must disclose the property's flood risk. This comes from Senate Bill 6237 (Chapter 234, Laws of 2026), signed by Governor Ferguson and added to Washington's Residential Landlord-Tenant Act (chapter 59.18 RCW).
The disclosure tells the tenant three things: that the property may sit in a special flood hazard area or an area of potential flooding, that your insurance policy does not cover the tenant's personal belongings, and that the tenant should consider flood insurance. You also have to point the tenant to county flood hazard information.
The law traces back to the December 2025 flooding in Western Washington, where renters lost belongings without knowing their homes were in floodplains or that standard renters insurance doesn't cover flood damage. Until this bill, Washington required flood disclosures when a home was sold but not when it was rented.
What you need to do: you have until the end of 2026, but the task is simple. Add a flood disclosure clause to your standard lease so every new lease signed in 2027 includes it. A generic lease template pulled off the internet won't have this language.
4. Privacy rules for smart access systems (January 1, 2027)
Starting January 1, 2027, Washington landlords who use smart access systems must follow new privacy rules under Engrossed Substitute Senate Bill 5937 (Chapter 55, Laws of 2026). A smart access system grants entry with key fobs, key cards, phone apps, fingerprints, or similar technology. The law limits how much data the system can collect to the minimum needed to let someone in, requires that tenants get access to the system's privacy policy, and requires that you offer an alternative key on request, such as a fob, card, physical key, or keypad code, so a tenant isn't forced to use biometrics or a phone app.
One thing to flag for single-family owners: the law applies to residential property under the Residential Landlord-Tenant Act, but much of its operative language is written around "smart access buildings" with shared entries, elevators, and common areas. If you own scattered single-family rentals, much of it reads as geared toward larger buildings rather than your front-door smart lock, though the underlying definitions are broad. The alternative-key and privacy-policy provisions still point to where tenant expectations are heading. If you use app-based or biometric entry, confirm with your attorney how the law applies to your specific setup.
What you need to do: note the January 2027 date and revisit it if you run any building-style or multi-unit property with shared smart access.
The bottom line
Between staggered effective dates, per-property exceptions, and local rules layered on top of state law, staying compliant in Washington is ongoing work, not a once-a-year update.
Two of the four changes are already in effect: the move to regular mail for notices, and the cooling-device rules, which require lease language only if you restrict window units. The flood disclosure can wait until you refresh your lease for 2027, and the smart access rules mostly matter if you operate multi-unit buildings.
If Doorstead manages your property, we handle lease compliance and notice service for you, so these changes are already on our radar. If you self-manage, the safest move is to have your lease and your notice process reviewed now and ahead of the 2027 effective dates.
Sources: Washington State Legislature bill pages for HB 2664, SB 6237, ESSB 6200, and ESSB 5937.