Buying a rental property in Washington: tenant rules

How does the rent cap work?

Under RCW 59.18.700, a landlord may not raise rent:

• during the first 12 months of a tenancy, or
• during any 12-month period by more than 7% plus the consumer price index (CPI), or 10%, whichever is less.

The CPI used is the June 12-month change for the Seattle area, and Commerce publishes each year’s maximum. The cap covers month-to-month and fixed-term tenancies alike, and it covers recurring charges as well as base rent: the statutory notice form says “rent” includes all recurring and periodic charges for use of the unit. A landlord may set any rent after a tenant moves out and the tenancy ends.

Example: a tenant pays $2,000 a month and the landlord increases the rent in 2026. The most the rent can be after that increase is $2,000 × 1.09683 = $2,193.66. A 2027 increase is capped at $2,200 on the same base.

Which rentals are exempt?

RCW 59.18.710 lets a landlord raise rent above the cap only for these tenancies, and the notice must state the facts supporting the exemption:

• A unit whose first certificate of occupancy was issued 12 years or less before the notice date.
• Units owned by housing authorities and certain nonprofits where rents are regulated, and qualified low-income housing tax credit developments.
• A unit where the tenant shares a bathroom or kitchen with an owner who lives on the property.
• A single-family owner-occupied home where the owner rents no more than two units or bedrooms, including an accessory dwelling unit.
• A duplex, triplex or fourplex where the owner lived in one unit at the start of the tenancy and still does.

The last three exemptions do not apply if the owner is a real estate investment trust, a corporation, or a limited liability company with at least one corporate member. A buyer who plans to rent out a house should check which category applies before pricing the rent.

A tenant who gets an unlawful increase must first give the landlord a written demand to reduce it. Tenants and the Attorney General can sue; a court awards excess rent paid, up to three months of unlawful charges, and attorneys’ fees, and the Attorney General can seek civil penalties of up to $7,500 per violation.

A 2026 bill, H.B. 2452, would change how rent increase notices are served. As of October 2026 the legislature’s page shows it was read and referred to committee on January 13, 2026, with no later action.

What notice does a landlord need?

• State rule: at least 90 days’ written notice of a rent increase, and the increase cannot take effect before the lease term ends (RCW 59.18.140). The notice must follow the form in RCW 59.18.720.
• Seattle rule: at least 180 days’ written notice before any increase in monthly housing costs, including recurring fees (Seattle Department of Construction and Inspections, SDCI).
• Seattle’s relocation assistance rules also apply to increases of 10% or more within 12 months, according to the City’s Renting in Seattle page.

What about security deposits?

A landlord can collect a deposit only if the rental agreement is in writing and the landlord gives a signed move-in checklist (RCW 59.18.260). Deposits go into a trust account at a financial institution located in Washington, and the tenant gets a written receipt (RCW 59.18.270). Within 30 days after move-out the landlord must send a full written statement of any amount withheld, with estimates or invoices, plus any refund (RCW 59.18.280). Landlords cannot withhold for ordinary wear.

Can a landlord end a tenancy?

Washington lists the only lawful reasons (“cause”) to end most tenancies (RCW 59.18.650). They include unpaid rent, a lease violation, and two reasons that matter to buyers and sellers:

• Owner or family occupancy: the owner or immediate family will live in the unit as a principal residence, with 90 days’ written notice.
• Sale of a single-family home: the owner elects to sell, with 90 days’ written notice. The law presumes the owner did not intend to sell if the home is not listed within 30 days after the tenant leaves.

A notice for unpaid rent allows 14 days for tenancies under this chapter (RCW 59.12.030(3)).

What are Seattle’s extra rules?

• Just Cause Eviction Ordinance. Seattle’s ordinance lists 16 approved reasons for ending or not renewing a tenancy. The landlord must state one and comply with the Rental Registration and Inspection Ordinance. Sale of a single-family home and owner occupancy each require 90 days’ notice.
• Rental registration. All Seattle rental owners must register their properties. SDCI inspects registered properties at least once every 5 to 10 years. Fee amounts are published by SDCI.
• Fees and agreements. Late fees are capped at $10 a month. Landlords may not charge for issuing notices, must give tenants the Renter’s Handbook, and must offer a reasonable renewal 60 to 90 days before a fixed-term lease ends unless there is just cause. SDCI cites Seattle Municipal Code chapter 7.24.
• Retaliation. Raising rent or evicting because a tenant filed a complaint or asserted rights is prohibited.

See the Seattle guide and seller disclosure in Washington for related rules.

What changes when you buy a home with a tenant?

The sections read here say that if the landlord changes during a tenancy, the deposit must be moved into the successor landlord’s trust account, and the new landlord must promptly tell the tenant where it is held (RCW 59.18.270). A buyer who plans to move in or resell must still use one of the lawful causes and notice periods above. Ask your attorney to review leases, deposits and the rent history before closing; see real estate attorney in Washington and closing costs.