Rent calculators
The Washington rent increase limit, new since 2025.
Washington joined the capped states in 2025. Seven per cent plus CPI, never above ten, with a manufactured home lot capped lower and buildings under twelve years old outside it. A state that had no ceiling the year before now has one.
Letting law is written below the country here, so the rules differ inside it.
It fixes the anniversary, and where an index applies, the starting index.
The anniversary you are claiming.
What the lease or the notice sets. A statutory ceiling brings it down where one applies.
The regional figure this jurisdiction publishes, not a national headline rate.
Rent today
$850.00
Revised rent
$875.50
The difference
+$25.50
$306.00 over a year
The working
$850.00 × (1 + 3,0 %) = $875.50
From 24 Sep 2026 the rent goes from $850.00 to $875.50, +$25.50 a month. There is no rent index here. United States, Washington caps the yearly rise at 7,0 % plus CPI, never above 10,0 % (HB 1217 (2025), RCW 59.18), and 3,0 % is what that comes to.
Check before you send
- No CPI was supplied, so the ceiling has been taken as 7,0 %, the fixed part of the formula alone. The lawful ceiling is that plus the CPI United States, Washington publishes, to a maximum of 10,0 %.
What governs in United States, Washington
- Index
- Statutory cap: 7% plus CPI, to 10%
- Formula
- new rent = current rent × (1 + the lower of (7% + CPI) and 10%)
- Statutory ceiling
- 10 %
Nobody here has read these rules in the law of United States, Washington yet, so every figure above is a plausible default rather than a confirmed one. Dardaris will not act on an unconfirmed rule on its own, and neither should you: check it in the source before you send anything.
Nothing is stored and nothing is sent. This runs the same calculation engine the product itself runs, in this browser.
What the rules actually say
The rules Dardaris applies in Washington.
Every line below is read off the same jurisdiction pack the product runs on, and each one says whether anybody has confirmed it in a source.
- Index
Statutory cap: 7% plus CPI, to 10%
The CPI is the one United States, Washington names, published for the region rather than nationally. Enter the published figure rather than a national headline rate.
Not confirmed in a source yet. Check it before you act on it.
- Formula
new rent = current rent × (1 + the lower of (7% + CPI) and 10%)
Seven per cent plus CPI, never above ten, for most units; a manufactured-home lot is capped lower. Buildings under twelve years old are exempt.
Not confirmed in a source yet. Check it before you act on it.
- Notice
A written demand is required
Written notice is required, and the period depends on the size of the rise and on how long the tenant has been there. Confirm it before you send.
Not confirmed in a source yet. Check it before you act on it.
- Back claim
Nothing can be back claimed
A rent rise runs from the date the notice takes effect and is never back-claimed in the United States.
Confirmed in a primary source
- Statutory ceiling
7 % plus CPI, never above 10 %
Seven per cent plus CPI, never above ten, for most units; a manufactured-home lot is capped lower. Buildings under twelve years old are exempt. Check the exemptions before relying on the ceiling: a dwelling outside the statute is not capped by it, and a city inside the state may cap lower.
Not confirmed in a source yet. Check it before you act on it.
The questions that follow.
- What is the Washington rent increase cap?
- Seven per cent plus the consumer price index, capped at ten per cent, under HB 1217 of 2025 in RCW 59.18. A manufactured home lot is capped lower.
- Which Washington rentals are exempt?
- Buildings under twelve years old sit outside the cap. An exempt unit is not capped at all, so confirm the age of the building before relying on the ceiling.
- What does Washington state rent increase law say now?
- That a rise is capped, which it was not before. The statewide cap is new, so guidance written before 2025, and the habits of landlords who have let here for years, both predate the law as it stands.
The same calculator, under other law.
A rent rises differently in each of these, and the page for each one says how. Anywhere else, the calculator still runs on that jurisdiction's own pack.
The calculation takes a minute. The date is what costs you.
Nobody forfeits a year because the arithmetic defeated them. They forfeit it because the anniversary fell in a quiet month, the index was not out yet, and by the time it was, there was nothing to remind them.
- It watches the anniversary for youDardaris holds the lease, its reference quarter and its anniversary, and tells you a revision is due rather than waiting to be asked.
- And works it out on the right two figuresThe reference quarter the lease names, against the same quarter a year earlier, applied to the rent in payment. The DPE block and the twelve month window are part of the same answer.
- But it does not send itA letter that raises somebody's rent waits for you. Dardaris prepares it and says what it is based on, and you are the one who decides it goes.
The number is the easy part.
Dardaris keeps the lease, raises the invoice, matches the payment and writes down what it did. Bring one building and watch a month before you decide anything.
14 days before the first charge · Nothing is switched on until you say so