Washington HB 1217 Rent Cap & CPI Formula — Compliance Guide for 2026

What Is HB 1217 and When Did It Take Effect?

Washington House Bill 1217, codified in RCW 59.18.140, established a statewide rent cap effective January 1, 2020. This law fundamentally changed how Washington landlords can increase rent. Unlike local rent control ordinances that apply only to specific cities, HB 1217 applies to all rental properties in Washington state with limited exceptions.

The statute reads: “A landlord shall not charge or receive rent, payment, deposit, or other consideration that is in violation of this section. Whenever there is an increase in the amount of rent, the landlord shall provide the tenant with advance written notice… of at least sixty days prior to the effective date of the increase.”

The law was prompted by rising housing costs across the state and tenant displacement in major metropolitan areas. It applies to all residential rental agreements for properties with one or more tenants, regardless of unit count or property type, subject only to the narrow exemptions discussed below.

How the 7% Cap and CPI Formula Work

The Two-Part Test: 7% or CPI + 1%, Whichever Is Lower

RCW 59.18.140(1) states that a landlord may not increase rent by more than the greatest of:

• Seven percent (7%) of the previous year’s rent, OR
• The percentage increase in the Consumer Price Index (CPI) for the Seattle-Tacoma-Bellevue metropolitan area, plus one percent (1%), whichever is lower

In practical terms, you calculate both numbers and use the lower of the two.

Which CPI Index Does Washington Use?

Washington specifically uses the Consumer Price Index for All Urban Consumers (CPI-U) for the Seattle-Tacoma-Bellevue metropolitan area, as published by the U.S. Department of Labor, Bureau of Labor Statistics. The calculation period runs from July of the previous year through June of the current year.

For the 2026 rent year (increases effective January 1, 2026 and forward), landlords use the 12-month CPI increase from July 2024 through June 2025. This creates a predictable, government-published benchmark that cannot be disputed or manipulated by individual landlords.

Real-World Calculation Example

Assume a tenant’s current annual rent is $1,200 per month ($14,400/year). The CPI-U for Seattle-Tacoma-Bellevue increased 2.8% over the July 2024–June 2025 measurement period.

Calculation:

• 7% of $1,200 = $84 per month increase
• CPI (2.8%) + 1% = 3.8% of $1,200 = $45.60 per month increase
• Allowed increase = $45.60 (the lower of the two)
• New monthly rent = $1,245.60

In this scenario, even though a 7% increase would be allowed under the statute’s upper limit, the CPI formula produces a lower number, so the CPI formula governs your increase.

Notice Requirements and the 60-Day Deadline

Statutory Notice Obligation

RCW 59.18.140(2) requires that “whenever there is an increase in the amount of rent, the landlord shall provide the tenant with advance written notice of at least sixty days prior to the effective date of the increase.”

This notice requirement is mandatory and non-waivable. Failure to comply means the increase cannot be enforced.

Timing and Service Requirements

Sixty-day window: The notice must reach the tenant no fewer than 60 days before the increase takes effect. If you send notice on January 1, the earliest you can enforce the increase is March 2 (60 days later).

Service methods: The notice must be delivered in writing. RCW 59.18.150 allows service by:

• Personal delivery to the tenant
• First-class mail sent to the tenant’s address on file
• Email, if the tenant has agreed to electronic notice (highly recommended for documentation)
• Any method permitted under the lease agreement

If you mail the notice, allow time for postal delivery. Many landlords send notices 75–90 days in advance to build in a safety margin for mail delays and to demonstrate good-faith compliance.

What the Notice Must Contain

The statute does not specify exact language, but your notice should clearly state:

• The current monthly rent amount
• The new monthly rent amount
• The dollar amount of the increase
• The effective date of the increase
• Reference to RCW 59.18.140 (optional but recommended for transparency)
• The CPI percentage used (if applicable)

Best practice: Use a dated, signed written notice; keep a copy in your records; and request signed acknowledgment from the tenant. This creates an auditable paper trail if the increase is later challenged.

Exemptions and Exceptions to the Rent Cap

Not every rental property in Washington is subject to HB 1217. The law has narrow carve-outs:

New Construction Exemption (First 5 Years)

RCW 59.18.140(1)(a) exempts buildings in which construction was completed less than 5 years before the date of the increase. This is intended to allow landlords to recover initial investment and financing costs.

Key point: The 5-year clock starts on the certificate of occupancy date, not the date the building was first rented. Once five years pass, the cap applies immediately to all future increases, even mid-lease.

Owner-Occupied Duplex, Triplex, or Fourplex Exemption

RCW 59.18.140(1)(b) exempts properties where the landlord occupies one unit and rents no more than two additional units in the same structure. The landlord must live on the property as their primary residence.

Compliance note: If you later move out or purchase a second property, this exemption ends, and you cannot claim it retroactively. Keep documentation of your residency status at the property.

Mobile Home Park Exemption (Conditional)

Mobile home parks where the landlord does not own the mobile homes themselves (only the land) have limited exemptions under other RCW provisions, but these do not override HB 1217 in most cases. Mobile home landlords should consult an attorney before assuming exemption.

What Is NOT Exempt

The following properties and situations are NOT exempt from the 7% cap:

• Single-family homes (if rented to a third party)
• Multi-unit buildings owned by investors
• Condominiums or townhomes rented by non-owner occupants
• Buildings more than 5 years old
• Any property with 3+ units in the same building (if owner-occupied)
• Luxury apartments or high-end rentals (the cap applies regardless of price)

Year-Over-Year Calculation and Measurement Periods

When Does the CPI Index Update?

Washington’s statute ties the CPI calculation to the July–June fiscal year. The most recent 12-month CPI-U figure for the Seattle-Tacoma-Bellevue area is published by the U.S. Department of Labor in mid-July each year.

For rent increases effective January 1, 2026, you use the CPI-U published in July 2025 (covering the July 2024–June 2025 period). For increases effective January 1, 2027, you use the CPI-U published in July 2026 (covering July 2025–June 2026), and so on.

How to Find the Official CPI Number

Visit the U.S. Department of Labor Bureau of Labor Statistics website (bls.gov) and search for “Seattle-Tacoma-Bellevue CPI-U 12-month.” The official series is Series ID CUUR49A0R00000SA (CPI-U for the Seattle-Tacoma-Bellevue Area).

Compliance tip: Screenshot or save the official BLS page showing the CPI figure you used. If a tenant disputes your increase, you can prove the number came from a government source, not your own calculation.

What Happens If Rent Increases Mid-Year?

If your lease renews on a date other than January 1, you still use the most recent published CPI-U figure at the time of the increase. For example, if you send a rent increase notice in August for an October 1 effective date, you use the CPI-U from the July publication (which covers the prior 12-month period).

Penalties for Non-Compliance and Tenant Remedies

What Happens If You Violate the 60-Day Notice Requirement?

If you serve notice with fewer than 60 days’ advance notice, or fail to serve notice at all, the rent increase is void and unenforceable. RCW 59.18.140(2) states: “The tenant may not be charged an increased amount of rent for the period until the 60 days have passed.”

This means:

• You cannot collect the increased amount
• If you collect it anyway, the tenant may withhold the overage from future rent payments
• The tenant can sue you for recovery of overcharges plus interest and attorney fees

What Happens If You Exceed the 7% Cap or CPI Formula?

If you attempt to increase rent beyond the statutory cap, the excess is an unlawful charge. RCW 59.18.140(1) makes it unlawful for a landlord to “charge or receive rent, payment, deposit, or other consideration that is in violation of this section.”

Tenant remedies include:

• Rent withholding: The tenant may withhold the overcharge from monthly rent payments without penalty
• Recovery action: The tenant can sue in small claims court (up to $10,000 in King County) or superior court for full recovery
• Treble damages or attorney fees: Depending on the nature of the violation and whether the tenant proves willful conduct, a court may award triple damages (3x the overcharge) and require you to pay the tenant’s attorney fees
• Lease termination: A pattern of illegal rent increases may give the tenant grounds to break the lease without penalty

Enforcement by State Agencies

The Washington Attorney General’s office and local prosecutors have authority to enforce RCW 59.18.140 under the state’s Consumer Protection Act (RCW 19.86). Violations can trigger:

• Civil penalties of up to $2,000 per violation
• Injunctions preventing further illegal increases
• Restitution orders requiring repayment of overcharges to affected tenants

Tenant advocacy organizations and legal aid clinics frequently audit landlord rent increase notices as part of systemic compliance reviews. A pattern of violations can expose you to class action exposure.

Documentation and Compliance Checklist

To protect yourself and demonstrate compliance, maintain the following records:

Pre-Increase Documentation

• CPI calculation worksheet: Document the official CPI-U figure you used, the date you accessed it, and the 7% alternative calculation, showing which was lower
• Rent history: Keep a record of the current month’s rent amount before the increase
• Exemption verification (if applicable): If you claim an exemption, document the property’s construction completion date or your occupancy status

Notice Documentation

• Notice letter with date and signature: Use a template and sign/date it before sending
• Proof of service: If mailed, keep the original envelope with postmark; if emailed, save the confirmation; if hand-delivered, request a signed receipt
• Service date log: Record exactly when the notice was delivered and to whom
• Copy retained: Keep a copy of the notice in your property file for at least 3 years

Post-Increase Tracking

• Lease amendment or acknowledgment: Have the tenant sign a lease amendment or acknowledgment confirming the new rent amount and effective date
• Rent payment records: Track that rent was paid at the new amount; discrepancies flag potential disputes
• Communication log: If the tenant disputes the increase, document all conversations and correspondence

LeaseBase’s Compliance Engine automatically tracks notice deadlines and CPI thresholds for your portfolio, flagging increases that exceed the statutory cap before you issue them.

Interaction With Other Tenant Rights Laws

Retaliation Protection

RCW 59.18.240 prohibits landlords from raising rent in retaliation for a tenant exercising legal rights (such as requesting repairs, joining a tenant organization, or reporting code violations). If a tenant has made a habitability complaint, you cannot increase rent within 6 months unless the increase is independently justified and documented.

Compliance strategy: If you plan a rent increase, time it to occur at least 6 months after any tenant communication about repairs or complaints. Maintain records showing the increase was planned independent of any complaint.

Move-In/Move-Out Protections

Some leases include clauses allowing rent increases mid-lease. HB 1217 supersedes these clauses. Even if your lease says “rent may increase without notice,” you must comply with the 60-day notice requirement and the 7%/CPI cap.

Common Compliance Mistakes and How to Avoid Them

Mistake #1: Using the Wrong CPI Index

Error: Landlords sometimes use the national CPI-U or the Seattle CPI-W (for wage earners) instead of the Seattle-Tacoma-Bellevue CPI-U.

Fix: Always verify you’re using the correct series ID (CUUR49A0R00000SA) from the official BLS website before calculating your increase.

Mistake #2: Failing to Account for the July–June Measurement Period

Error: Using calendar-year CPI (January–December) instead of the July–June fiscal year required by statute.

Fix: Mark your calendar for July each year to check the updated CPI-U figure, and note which measurement period applies to your January 1 rent increase.

Mistake #3: Sending Notice Too Close to the Effective Date

Error: Serving a rent increase notice on December 15 with a January 1 effective date (only 17 days’ notice). The increase is void.

Fix: Set a reminder 90 days before your lease renewal to calculate and send notice. Use email with read receipts to ensure timely service.

Mistake #4: Claiming an Exemption You Don’t Qualify For

Error: A landlord claims the owner-occupied duplex exemption but actually rents three units. The exemption does not apply; the 7% cap governs all three units.

Fix: Before claiming any exemption, consult the specific statute language or an attorney. Document your exemption status (e.g., certificate of occupancy date, occupancy declaration) in your records.

Mistake #5: Not Recalculating When the Tenant’s Lease Renews

Error: A tenant’s lease renews February 1 each year. You calculate the increase in January using that month’s rent as the baseline, but you fail to adjust for any interim increases from the prior year.

Fix: Always use the rent amount the tenant is actually paying immediately before the increase takes effect. If there was a prior increase, use that higher amount as your baseline.

Practical Checklist: How to Comply With HB 1217

Task	Timeline	Compliance Note
Check current rent amount in lease	4 months before increase	Verify the baseline amount you’ll calculate from
Verify property exemption status	4 months before increase	Confirm construction date or owner-occupancy; document in file
Obtain current CPI-U figure	3 months before increase	Visit bls.gov; screenshot the figure; note the measurement period
Calculate 7% cap and CPI + 1% formula	3 months before increase	Document both calculations; identify the lower amount
Draft and sign notice letter	3 months before increase	Include current rent, new rent, dollar amount, effective date, and CPI reference
Serve notice on tenant (email preferred)	At least 60 days before increase	Use email with read receipt; keep proof of delivery
File copy in property record	Immediately after service	Include notice, proof of service, and CPI documentation
Collect new rent amount at effective date	On or after effective date	Track in rent ledger; flag any shortpayments
Retain records for 3+ years	Ongoing	Prepare for tenant disputes, tax audits, or attorney general inquiries

Frequently Asked Questions

Q: Can I charge different rent increases to different tenants in the same building?

A: Yes, but only if the increases comply with the statutory cap independently for each tenant. If both tenants are in the same building and their leases renew on the same date, you can increase each by up to the 7%/CPI cap based on their individual current rent. However, you cannot use different CPI figures or calculations to justify different rates. Calculate each tenant’s increase separately; the cap applies to each.

Q: What if the CPI-U is negative (deflation)?

A: The statute allows increases of the greater of 7% or CPI + 1%. If CPI is negative (e.g., −2%), then CPI + 1% = −1%, which is lower than 7%. In this case, you can still increase rent by 7%. However, negative CPI is rare in recent history. Keep the statute’s wording in mind: you can increase rent by the “greatest of” the two figures, not the lowest.

Q: If I own a property in Washington and another state, are both subject to HB 1217?

A: Only properties in Washington are subject to RCW 59.18.140. Properties in other states follow that state’s rent control laws (if any). Make sure you track which properties fall under which jurisdiction and apply the correct rules to each.

Q: Can I include utilities or services in the rent to avoid the cap?

A: No. The statute applies to “rent, payment, deposit, or other consideration.” Attempting to reclassify a portion of rent as a separate “service fee” or “utility charge” to circumvent the cap is an unfair practice. All charges for occupancy must be included in the rent calculation for purposes of the 7%/CPI cap. Washington courts and the Attorney General’s office have made clear that form-over-substance reclassification violates the statute’s intent.

Q: What if my tenant doesn’t respond to the rent increase notice? Am I compliant?

A: Yes. You are compliant if you provide proper written notice at least 60 days before the effective date, regardless of whether the tenant responds, disputes, or acknowledges it. However, if the tenant does not pay the new amount on the effective date, be prepared to enforce it (or negotiate) and document your efforts. Keep proof of service in case the tenant later claims they never received notice.

How LeaseBase Helps You Stay Compliant

Self-managing landlords juggling multiple properties can lose track of lease renewal dates, CPI changes, and notice deadlines. LeaseBase’s Compliance Engine flags when rent increases are due, automatically calculates the 7% cap and current CPI+1% threshold, and prevents you from issuing an increase that exceeds the cap. The platform also logs notice dates and stores service documentation in your property’s file, so you have proof of compliance if a tenant ever disputes the increase.

For portfolios with 5+ units, Rent Payment tracking lets you monitor whether tenants are paying at the new rate, and Analytics & Reporting generates year-over-year rent data to help you plan future increases based on actual CPI trends.

Disclaimer

This article is for informational purposes only and does not constitute legal advice. Consult a qualified attorney for guidance specific to your situation. Rent control law changes frequently, and local ordinances may impose stricter limits than state law. Always verify the current version of RCW 59.18.140 and consult a Washington-licensed attorney if you are unsure whether an exemption applies or how to calculate a compliant increase.