Washington's first rent cap under HB 1217 took effect July 1, 2025. It limits rent increases to 7% + CPI (max 10% total) for most residential units built before February 1, 2005. The cap applies per 12-month period with no banking of unused increases. Landlords who exceed the cap face void increases, tenant damages, and potential AG enforcement.
What HB 1217 Does
House Bill 1217 represents the most significant change to Washington's rental market in a generation. For the first time, the state has imposed a ceiling on how much landlords can raise rent in a given year.
Before HB 1217, Washington had no rent control or stabilization laws. Landlords could raise rent by any amount with proper notice. HB 1217 changed that by establishing a formula-based maximum that balances landlord costs (via the CPI inflation adjustment) with tenant affordability (via the hard cap).
The law took effect on July 1, 2025, and applies to rent increases with effective dates on or after that date.
The Rent Cap Formula
How It's Calculated
The maximum allowable rent increase under HB 1217 is:
Base rate: 7% Plus: CPI-U for Seattle-Tacoma-Bellevue MSA (most recent 12-month period) Hard ceiling: 10% total
The CPI component uses the Consumer Price Index for All Urban Consumers (CPI-U) for the Seattle-Tacoma-Bellevue metropolitan statistical area, as published by the U.S. Bureau of Labor Statistics (BLS).
Practical Examples
Here's how the formula works in practice at different CPI levels:
| CPI-U Rate | Formula | Maximum Increase |
|---|---|---|
| 1.5% | 7% + 1.5% = 8.5% | 8.5% |
| 2.0% | 7% + 2.0% = 9.0% | 9.0% |
| 3.0% | 7% + 3.0% = 10.0% | 10.0% (at the cap) |
| 4.5% | 7% + 4.5% = 11.5% | 10.0% (hard ceiling applies) |
| 0.5% | 7% + 0.5% = 7.5% | 7.5% |
The CPI-U for the Seattle-Tacoma-Bellevue area is published monthly by the BLS. For rent cap calculations, use the most recent 12-month percentage change available at the time you calculate the increase. The BLS typically publishes this data with a one-month lag.
Dollar Amount Example
For a unit currently renting at $1,800/month with a CPI of 2.3%:
- Maximum percentage: 7% + 2.3% = 9.3%
- Maximum dollar increase: $1,800 x 9.3% = $167.40
- Maximum new rent: $1,967.40
Rounding to the nearest dollar is standard practice, so the maximum new rent would be $1,967/month.
Which Properties Are Covered
Properties Subject to the Cap
HB 1217 applies broadly to residential rental properties in Washington:
- Multifamily apartments built before February 1, 2005
- Single-family rental homes (when the owner does not reside on the property)
- Duplexes, triplexes, and fourplexes with 4+ rental units on the property
- Manufactured housing communities (for space rent)
- Condominiums and townhouses offered for rent
Exempt Properties
Several categories of properties are exempt from the rent cap:
1. New Construction (Post-2005)
Units that received their certificate of occupancy on or after February 1, 2005 are exempt. This exemption is designed to avoid discouraging new housing development. The date is based on the certificate of occupancy, not the construction start date or building permit date.
2. Subsidized Housing
Units where rent is set by a government housing program (Section 8 project-based, LIHTC during compliance period, public housing) are exempt. However, units that simply accept Housing Choice Vouchers (Section 8 tenant-based) are NOT exempt — the landlord's portion of the rent is still subject to the cap.
3. Small Properties
Properties with fewer than 4 units may qualify for exemption in certain circumstances. This is intended to exclude small "mom and pop" landlords who rent out a portion of their own property.
4. Owner-Occupied Properties with ADU
An owner-occupied single-family home with an accessory dwelling unit (ADU) is exempt from the cap for the ADU rent.
5. Substantial Rehabilitation
Units that have undergone substantial rehabilitation meeting specific cost thresholds may qualify for a temporary exemption, similar to new construction. The rehabilitation must represent a significant capital investment relative to the property's assessed value.
Exemption status is property-specific, not owner-specific. A landlord may have some properties subject to the cap and others that are exempt. Each property must be evaluated independently based on its construction date, size, and other characteristics.
No Banking of Unused Increases
One of the most frequently asked questions about HB 1217 is whether landlords can "bank" or accumulate unused increase capacity.
The answer is no.
Each 12-month period is evaluated independently. If you increase rent by only 3% this year and the cap would have allowed 9%, you cannot carry the unused 6% forward. Next year's maximum is still calculated fresh from the formula.
This has important strategic implications:
- Under-increasing in one year cannot be recovered later — you permanently lose that revenue potential
- Each annual increase should be carefully considered against the current cap
- Waiting multiple years and then imposing a large "catch-up" increase is not permitted if it exceeds the current year's cap
The 12-Month Rule
Rent can only be increased once in any 12-month period per tenancy. This is a separate requirement from the cap itself — even if you're under the cap, you cannot increase rent more frequently than once every 12 months.
Enforcement and Penalties
What Happens If You Exceed the Cap
Landlords who impose rent increases exceeding the HB 1217 maximum face several consequences:
1. Void Increase The portion of the increase exceeding the cap is void and unenforceable. The tenant is only obligated to pay up to the maximum allowable rent. If a landlord attempts to collect the excess, the tenant has legal grounds to refuse.
2. Tenant Remedies Tenants may pursue:
- Recovery of any excess rent paid
- Actual damages incurred due to the improper increase
- Reasonable attorney fees and court costs
- The right to remain at the properly capped rent
3. Attorney General Enforcement The Washington Attorney General's office may investigate and pursue enforcement actions against landlords who systematically violate the rent cap. This can include civil penalties and injunctive relief.
4. Local Enforcement Some municipalities, including Tacoma and Seattle, have their own enforcement mechanisms that may provide additional remedies beyond state law.
Ignorance of the cap is not a defense. Property managers and landlords are expected to know the current maximum allowable increase and to calculate it correctly. Using a compliance tool like NoticePM that automatically verifies your proposed increase against the current cap can protect you from inadvertent violations.
How HB 1217 Interacts with Notice Requirements
The rent cap exists alongside — not instead of — the notice requirements under RCW 59.18.140 and HB 1003. Compliance requires satisfying both the cap and the notice requirements:
| Requirement | What It Governs | Source |
|---|---|---|
| Rent cap | How much you can increase | HB 1217 |
| Notice period | How far in advance you must notify | RCW 59.18.140 (90 days) |
| Certified mail | How you must deliver the notice | HB 1003 |
| Mailing rule | Additional days for mail service | RCW 59.12.040 (5 days) |
| Statutory form | What the notice must contain | RCW 59.18.720 |
| Tacoma extras | Additional 180-day notice | TMC 1.95 |
Rent Cap Disclosure on the Notice
Under RCW 59.18.720, the statutory rent increase notice must include information about the rent cap calculation. This means the notice itself must show:
- The current CPI-U rate used
- The maximum allowable percentage (7% + CPI)
- Whether the property is exempt from the cap (and why)
- The actual proposed increase percentage
This disclosure requirement means that even preparing the notice requires knowledge of the current CPI figure and the exemption analysis.
Practical Compliance Steps
Step 1: Determine If Your Property Is Subject to the Cap
Check the certificate of occupancy date. If the property was built (certificate issued) before February 1, 2005, it is almost certainly subject to the cap unless another exemption applies.
Step 2: Look Up the Current CPI-U
Visit the Bureau of Labor Statistics website and find the most recent 12-month CPI-U for the Seattle-Tacoma-Bellevue MSA. This figure changes monthly.
Step 3: Calculate the Maximum
Apply the formula: 7% + CPI-U = Maximum (capped at 10%). Calculate the maximum dollar increase from the current rent.
Step 4: Set Your New Rent
Set the proposed new rent at or below the calculated maximum. Consider strategic factors: market conditions, tenant retention, and the fact that unused capacity cannot be banked.
Step 5: Prepare the Notice with Cap Disclosures
Use the statutory form (RCW 59.18.720) and include the rent cap calculation showing the CPI-U rate, the maximum allowable percentage, and your proposed percentage.
Step 6: Send via Certified Mail
Mail the notice via certified mail from within Washington State at least 95 days before the effective date. For Tacoma properties, also send the 180-day TMC 1.95 notice.
Compliance Checklist
Looking Ahead: Will the Cap Change?
HB 1217 was passed with the formula set at 7% + CPI (max 10%). While there have been discussions about adjusting the formula — some tenant advocates push for a lower cap while landlord groups argue for adjustments — no changes have been enacted as of early 2026.
The law does not include a sunset clause, meaning it remains in effect indefinitely unless the legislature amends or repeals it. Given the current political landscape in Washington, the cap is likely to remain in place for the foreseeable future.
Property managers should build the rent cap into their long-term financial models. Assuming 2-3% CPI, the practical maximum increase in most years will be 9-10%. For properties where the current rent is significantly below market, the cap means it may take several years of maximum increases to reach market rate.
How NoticePM Helps with Rent Cap Compliance
NoticePM automates the rent cap verification process so you never accidentally exceed the HB 1217 maximum:
- Automatic CPI lookup — pulls the latest Seattle-Tacoma-Bellevue CPI-U figure
- Real-time cap calculation — shows the maximum allowable increase when you enter a proposed rent
- Exemption tracking — flags properties built after 2005 as potentially exempt
- Statutory form generation — pre-fills rent cap disclosures on the RCW 59.18.720 notice form
- 12-month frequency check — warns if a rent increase was already implemented within the past 12 months
Skip the paperwork. Let NoticePM handle compliance.
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