Washington Sets the 2026 Rent Increase Cap at 9.683%

Washington's cap formula sets the maximum at 7% plus CPI, or 10%, whichever is less; for 2026, the 7%-plus-CPI calculation itself produced 9.683%, a figure below 10%, so that calculated number is what actually governs.

[Cite: RCW 59.18.700, as established by H.B. 1217, 2025 Wash. Sess. Laws, c. 209; Wash. Dept. of Commerce, 2026 rent increase cap announcement, July 18, 2025]

That distinction matters for understanding how the law behaves year to year; in a year where inflation is lower, the formula's own math, not the statutory backstop, sets the effective cap, which is exactly what happened here.

The prior year, 2025, saw the raw 7%-plus-CPI calculation reach 10.8%, which exceeds the statutory 10% maximum, so the lower 10% ceiling applied that year instead of the higher calculated figure.

[Cite: RCW 59.18.700; Wash. Dept. of Commerce, 2025 rent increase cap announcement]

Comparing the 2 years side by side shows the formula working exactly as designed; when inflation pushes the raw calculation above 10%, the ceiling takes over, and when it doesn't, as happened for 2026, the calculated number itself becomes the applicable cap.

The Department of Commerce publishes each year's applicable cap shortly after the Bureau of Labor Statistics releases its June Consumer Price Index data in mid-July.

[Cite: Wash. Dept. of Commerce, 2026 rent increase cap announcement]

That timing explains why landlords see this figure announced in July rather than earlier in the year; a landlord trying to anticipate the following year's cap before Commerce's own announcement would be working from incomplete data, since the calculation depends on a federal data release that doesn't happen until mid-July.

The statute itself sets the formula; the Department of Commerce is the entity responsible for calculating and publishing the actual applicable percentage each year based on that formula.

[Cite: RCW 59.18.700]

That division of responsibility means a landlord looking for the current year's specific cap percentage should check the Department of Commerce's published figure directly, rather than trying to independently recalculate it from raw CPI data, since Commerce's published number is the authoritative source landlords and tenants actually rely on.

The cap governs the maximum rent increase for any 12-month period, not simply increases imposed at the start of a calendar year.

[Cite: RCW 59.18.700]

A landlord raising rent at any point during 2026 needs to measure that increase against whatever rent was in effect 12 months earlier, applying the 9.683% ceiling to that full 12-month comparison, rather than assuming the cap only governs increases that happen to land on January 1.

Since the cap is recalculated annually from the prior 12 months of CPI data, a landlord shouldn't treat 9.683% as a stable, ongoing figure; the following year's cap, 2027's, actually did hit the full 10% ceiling again, showing how much the applicable number can swing from one year to the next.

[Cite: RCW 59.18.700; Wash. Dept. of Commerce, 2027 rent increase cap announcement]

A landlord planning multi-year rent strategy should build in the expectation that this percentage moves meaningfully year over year, rather than assuming whatever applied last year, or this year, will simply carry forward.

Since this percentage is recalculated and republished annually rather than fixed permanently in statute, a landlord needs to check the Department of Commerce's current published figure before finalizing any rent increase, rather than relying on a prior year's cap.

[Cite: RCW 59.18.700]

A landlord planning a 2026 rent increase based on an outdated 2025 figure risks either underpricing relative to what's actually allowed, or, more seriously, planning an increase that exceeds whatever the current year's actual published cap turns out to be.

This percentage cap is one piece of House Bill 1217's broader framework, which also includes a 90-day rent-increase notice requirement delivered on a specific state form.

[Cite: RCW 59.18.700; H.B. 1217, 2025 Wash. Sess. Laws, c. 209]

A landlord planning a rent increase within this 9.683% cap still has to separately satisfy that 90-day notice requirement using the correct statutory form; staying within the percentage cap alone doesn't substitute for meeting the law's separate notice and timing obligations.

Since the cap applies to any 12-month period rather than a fixed calendar window, a landlord benefits from clearly documenting exactly which 12-month period and prior rent figure a given increase is being measured against.

[Cite: RCW 59.18.700]

A landlord who can show precisely which earlier rent figure and date a current increase is being compared to is in a much stronger position if a tenant or regulator later questions whether a specific increase actually stayed within the applicable cap.

A landlord planning to raise rent at the start of calendar year 2026 should apply this 9.683% cap immediately, while a landlord planning a later 2026 increase should still confirm this remains the correctly applicable published figure at the time of that later increase.

[Cite: RCW 59.18.700]

Since Commerce republishes this figure annually, a landlord executing a rent increase later in 2026 should still be working from this same calendar-year-2026 published cap, but should confirm no updated guidance has superseded it before finalizing that later increase.

The practical starting point is updating internal rent-increase planning tools and templates to reflect the 9.683% maximum for any 12-month period in 2026.

Building a standard process for checking the Department of Commerce's published figure each July, right after the Bureau of Labor Statistics data release, rather than relying on institutional memory of a prior year's number, keeps a portfolio's rent-increase planning aligned with the correct, currently applicable cap going forward.