Washington HB 1217 Rent Cap: 7% Limit & CPI Formula Explained — 2026 Compliance Guide

What Is HB 1217 and When Did It Take Effect?

Washington’s House Bill 1217, codified in RCW 59.18.140, established the first statewide rent control measure in Washington history. The law took effect on January 1, 2024, and applies to all residential tenancies in the state—with limited exceptions.

The core rule is straightforward but requires precise calculation: landlords cannot increase rent by more than 7% or the Consumer Price Index plus 1%, whichever is lower. This is a hard ceiling, not a guideline. Rent increases that exceed this threshold are void and unenforceable, regardless of lease language or tenant agreement.

For self-managing landlords in Washington, this law fundamentally changes how you set rents at renewal. You can no longer charge whatever the market will bear. You must perform a calculation each year, document it, provide advance notice, and be prepared to defend your math if challenged.

The 7% Flat Cap vs. CPI + 1%: Which One Applies?

HB 1217 uses a “whichever is lower” formula. This means you calculate both amounts and use the smaller one.

The 7% Flat Cap

If you increase rent by 7% or less, you are compliant—period. No other calculation required. For example:

• Current rent: $1,200/month
• 7% of $1,200 = $84
• New rent ceiling: $1,284/month

This is the simpler path for most landlords. If your desired increase is 7% or under, you do not need to track CPI data.

The CPI + 1% Formula

Washington uses the Consumer Price Index for All Urban Consumers (CPI-U) for the Seattle-Tacoma-Bellevue area, published monthly by the U.S. Bureau of Labor Statistics. The annual CPI figure used for rent calculations is determined as of December 31 of the prior year.

The formula is:

Annual Rent Increase Cap = (CPI-U + 1%) applied to current rent

Washington’s Department of Housing and Community Development (DHCD) publishes the allowed rent increase limit annually by December 1 for the following calendar year. For 2026, the DHCD must publish the limit by December 1, 2025.

Example with real numbers (2025 calculation):

• CPI-U for Seattle-Tacoma-Bellevue (December 2024): 2.8%
• CPI + 1% = 2.8% + 1% = 3.8%
• Comparison: 7% vs. 3.8% → 3.8% is lower
• Maximum allowable increase: 3.8%
• Current rent: $1,500/month
• New rent ceiling: $1,500 × 1.038 = $1,557/month

In low-inflation years (like 2024–2025), the CPI formula typically produces a lower cap than 7%, which is why tenants’ rights advocates pushed for this law during a period of high inflation.

How to Find the Official Limit

Do not calculate CPI yourself. Instead:

1. Visit the Washington Department of Housing and Community Development website (deptofhcd.wa.gov)
2. Look for the annual rent increase limit notice, typically published by December 1
3. Use the officially published percentage for all rent increases effective in that calendar year

Using the wrong CPI figure—even if your calculation is mathematically correct—creates liability. The state’s official notice establishes the legal standard for that year.

The 90-Day Notice Requirement: Timing and Content

You cannot simply raise rent on renewal. RCW 59.18.140 requires written notice at least 90 days before the rent increase takes effect. Failure to provide this notice voids the entire rent increase.

When to Send Notice

Count backward 90 days from the date the new rent becomes effective. For a lease renewing January 1, 2027, you must provide notice by October 3, 2026 (90 days prior).

Send notice via certified mail, email (if tenant has agreed to electronic notice), or personal delivery. Document the delivery method and date. If the tenant contests the increase later, you will need proof of timely notice.

What the Notice Must Include

The notice must state:

• The amount of the current rent
• The amount of the new rent
• The dollar amount of the increase
• The percentage increase
• The effective date of the increase
• A statement that the increase complies with RCW 59.18.140 (optional but recommended)

Language example:

“Dear [Tenant Name], This is notice that your monthly rent will increase from $1,500 to $1,557 effective January 1, 2027. This is an increase of $57 per month, or 3.8%, which complies with Washington’s rent increase limit under RCW 59.18.140. This notice is provided 90 days in advance as required by law.”

The notice does not need to cite the CPI calculation or explain the formula—only state the current and new amounts and the percentage. However, including a reference to legal compliance strengthens your position if the tenant disputes the increase.

Consequences of Improper or Late Notice

If you fail to provide 90-day notice:

• The rent increase is void
• Rent remains at the prior amount until proper notice is given and a new 90-day period expires
• You cannot collect the higher amount retroactively
• Tenant has grounds to assert an affirmative defense in an eviction action if you attempt to collect

This is a strict requirement. Courts have no discretion to waive the 90-day notice period.

Exemptions to the HB 1217 Rent Cap

The 7% cap does not apply to all housing. HB 1217 exempts:

1. New Construction (Less Than 5 Years Old)

Residential buildings completed less than 5 years before the rent increase are exempt from the cap. This exemption expires 5 years after the certificate of occupancy date (or completion date).

Compliance note: You must be able to prove the completion date. Keep the building permit, certificate of occupancy, or contractor documents. If a tenant disputes the exemption, the burden is on you to demonstrate the building qualifies.

2. Mobile Home Parks

RCW 59.20 governs mobile home parks separately. However, the application of HB 1217 to mobile home tenancies remains subject to ongoing interpretation. Consult your mobile home park’s legal advisor before implementing rent increases above 7%.

3. Subsidized or Publicly Funded Housing

Housing where rent is set by a government subsidy program (such as Section 8, public housing, or other federally or state-funded programs) may be exempt if the rent is determined by the subsidy program rather than landlord choice. However, the tenant’s share of rent (if any) is still subject to HB 1217.

4. Owner-Occupied Duplexes and Single-Family Homes (Uncertain)

The statute does not explicitly exempt owner-occupied properties. Legal interpretations differ. To be safe, apply the cap to all residential tenancies unless your property clearly falls within one of the named exemptions above. Some landlords argue that a duplex where the owner occupies one unit is exempt, but this has not been tested in court under HB 1217.

Risk mitigation: If you own and live in part of a building, consult an attorney before imposing an increase above 7%. The cost of legal advice is far less than exposure to treble damages.

Penalties for Violating HB 1217

The consequences of charging rent above the legal limit are severe and are designed to deter violations.

Tenant Remedies Under RCW 59.18.150

If you violate the rent cap, the tenant can sue you for:

• Treble damages (3x the overcharged amount) — If you overcharged $1,000, the tenant can recover $3,000
• All attorney fees and court costs — You pay the tenant’s legal fees even if you win on some issues
• Any other relief a court deems appropriate

Example: A tenant pays an illegal increase of $57/month for 12 months = $684 overcharged. The tenant sues and wins. Damages = $684 × 3 = $2,052, plus attorney fees (commonly $2,000–$5,000) and court costs ($500–$1,500). Total exposure: $4,500–$8,500.

There is no “good faith” defense. If you charged above the cap, you are liable regardless of intent.

Tenant’s Right to Withhold Payment

Tenants have the right to refuse payment of any amount above the legal limit. If you attempt to evict for non-payment of an illegal increase, the eviction will be dismissed, and you may be ordered to pay the tenant’s attorney fees for defending against a frivolous case.

No “Cure” Period

Unlike some landlord-tenant violations, there is no opportunity to withdraw an illegal rent increase notice and avoid liability. Once the notice is served, the damage is done from a legal standpoint.

Step-by-Step Compliance Checklist for Annual Rent Increases

Use this checklist to ensure compliance before every rent increase:

Action Item	Deadline/Frequency	Compliance Status
Obtain the current CPI-U for Seattle-Tacoma-Bellevue from DHCD or BLS	By December 1 of prior year (DHCD publishes official limit)	☐
Calculate: CPI + 1%	Before finalizing rent increase	☐
Compare CPI + 1% to 7%; use the lower amount	Before finalizing rent increase	☐
Calculate new rent amount (current rent × approved percentage)	Before sending notice	☐
Send written 90-day advance notice (certified mail or electronic)	90 days before increase effective date	☐
Include in notice: current rent, new rent, dollar increase, percentage, and effective date	Same as notice date	☐
Document proof of notice delivery (tracking number, read receipt, or signature)	Same as notice date	☐
File notice copy in tenant file or property management system	Same as notice date	☐
Confirm tenant acceptance of new rent amount or prepare for dispute	30 days after notice date	☐
If tenant disputes: collect all supporting documentation (CPI source, lease, prior notices)	Upon dispute or threat of legal action	☐

Real-World Scenarios: How to Apply the Cap

Scenario 1: CPI Is Low, 7% Cap Applies

Situation: It’s 2026. DHCD announces the CPI + 1% limit is 2.5%. Your tenant’s lease renews January 1, 2027. Current rent is $1,800/month.

Calculation:

• CPI + 1% = 2.5%
• 7% flat cap = 7%
• Lower amount: 2.5%
• Maximum new rent: $1,800 × 1.025 = $1,845/month
• Increase: $45/month or 2.5%

Notice to tenant (by October 3, 2026): “Your rent will increase from $1,800 to $1,845, effective January 1, 2027. This is a $45 increase (2.5%), which complies with Washington’s rent increase limit.”

Scenario 2: Multiple Properties, One Renewal Date

Situation: You own 8 rental units. Three renew January 1, 2027. Others renew on different dates. What deadline do you use?

Answer: Each lease renewal has its own 90-day deadline. For the three January 1 renewals, you must send notice by October 3, 2026. For leases renewing April 1, 2027, the deadline is January 1, 2027. The cap percentage (CPI + 1% or 7%) is the same for all tenants for the same calendar year, but the notice dates differ by lease.

Scenario 3: Tenant Disputes the Increase

Situation: You send proper notice of a 3.8% increase. Tenant responds: “I’m not paying it. That’s not what the CPI was.” Tenant refuses to pay above the prior amount.

Your options:

1. Verify your CPI calculation. Provide the tenant with a copy of the DHCD’s official rent increase limit notice for 2026. If your increase matches, you are compliant.
2. Do not attempt to evict for non-payment of the disputed increase. The eviction will fail, and you’ll pay the tenant’s attorney fees.
3. Accept the tenant’s payment at the prior rate, or negotiate. You have the right to the increase, but enforcing it through eviction is not viable if the tenant disputes it in good faith.
4. Consult an attorney. If the tenant’s objection appears baseless, an attorney can send a demand letter or pursue a civil claim for the overdue portion after the tenancy ends.

How to Track and Document Compliance

Record-keeping protects you if a tenant sues or if your eviction is contested. Maintain the following for each property and each renewal:

• Lease agreement — signed copy showing original rent and renewal dates
• DHCD rent increase limit notice for the applicable year — downloaded and dated
• Written calculation — showing current rent, CPI %, 7%, and the lower amount selected
• Rent increase notice to tenant — with current rent, new rent, dollar and percentage increase, and effective date
• Proof of notice delivery — certified mail tracking, email read receipt, or personal delivery signature (dated at least 90 days before effective date)
• Tenant’s response or acceptance — email, letter, or payment at new rate

Digital storage (cloud backup) is recommended. If a lawsuit occurs, your attorney will need these documents within 24 hours. Spreadsheets are acceptable if they clearly show the calculation and the source of CPI data.

LeaseBase’s compliance engine can automate tracking of rent increase deadlines and store documentation in a centralized, audit-ready format. Self-managing landlords often use spreadsheets, which work but create gaps during disputes. A platform designed for compliance tracking reduces the risk of missing a 90-day deadline or losing proof of notice.

Common Mistakes and How to Avoid Them

Mistake 1: Using the Wrong CPI Index

Washington specifies the CPI-U for Seattle-Tacoma-Bellevue. Do not use the national CPI or a different metro area’s CPI. The DHCD’s official notice will specify the exact figure. Use only that.

Mistake 2: Rounding Errors in Rent Calculation

If your calculation yields $1,557.42, you can round to $1,557 or $1,558 (both common rounding methods). However, document which way you rounded. A tenant could argue you rounded up to exceed the cap. Transparency eliminates this issue.

Mistake 3: Verbal Notice Only

Text messages, phone calls, and verbal conversations do not satisfy the written notice requirement. Use certified mail, email (if agreed to in lease), or hand-delivery with a signed receipt. Do not rely on verbal notice, even if the tenant acknowledges it.

Mistake 4: Timing the Notice from the Wrong Date

Count 90 days backward from the date the new rent takes effect, not from the lease renewal date. If a lease renews January 1 but the new rent is effective January 15, count back from January 15, not January 1. A 90-day notice would be due by October 17 in this case.

Mistake 5: Assuming “Increase” Means Year-Over-Year from Lease Start

The cap applies to the increase from the current rent to the new rent at renewal. If a tenant’s rent was $1,200 when they signed the lease 3 years ago, and it’s now $1,500, you cannot increase it by another 7% just because you only raised it 2% last year. The cap is per renewal, not cumulative.

Mistake 6: Not Accounting for Exemptions Properly

If you claim a new construction exemption, have proof. If a tenant challenges it and you cannot show the completion date, you lose the exemption defense retroactively. The tenant may sue for treble damages on any overcharged rent.

What If You Charged Above the Cap Before 2024?

HB 1217 took effect January 1, 2024. Rent increases imposed before that date are not subject to this law, even if they exceeded 7%. However, any increases effective January 1, 2024, or later must comply.

If a tenant has a lease with a 2% annual increase clause and the 2024 increase kicks in on January 1, 2024, your increase must comply with the 7% cap (or CPI + 1%, whichever is lower), regardless of the lease language.

Federal vs. State Protections: HB 1217 and Eviction Prevention

Washington has no federal rent control—only state and local. HB 1217 is state law. Some Seattle and Tacoma residents live in cities with additional local ordinances (e.g., Seattle’s eviction protection in 2016–2018 laws). These are separate from HB 1217 and may offer additional protections. Check your city’s municipal code.

HB 1217 does not prevent eviction for cause (non-payment, lease violation). It only limits the amount of rent you can charge at renewal.

FAQ: HB 1217 Rent Cap Questions

Q1: If I own property outside Washington, does HB 1217 apply?

No. HB 1217 applies only to residential tenancies in Washington. If you own rental property in Oregon, Idaho, or California, Washington’s rent cap does not apply. However, those states may have their own rent control laws (e.g., Oregon’s statewide rent cap under ORS 90.322–90.323; California’s AB 1482 and AB 34).

Q2: Can I require a tenant to agree to waive HB 1217 protection?

No. RCW 59.18.140 cannot be waived by agreement. Any lease clause that attempts to override the rent cap is void and unenforceable. Attempting to have a tenant waive this protection exposes you to civil liability.

Q3: What if my lease says rent will increase by 10% automatically at renewal?

The lease clause is void to the extent it exceeds the HB 1217 cap. If the cap is 3.8%, the rent can increase by only 3.8%, regardless of lease language. The tenant is not required to pay the excess 6.2%.

Q4: If I do not renew the lease and the tenant leaves, do I owe rent at the old rate or can I charge the new tenant more?

HB 1217 applies to rent increases for existing tenants at renewal, not to rent charged to new tenants. You can charge a new tenant any amount the market will bear (subject to fair housing laws). The cap applies when you renew a tenancy—i.e., the tenant stays and the lease extends or is replaced with a new lease.

Q5: Can I use HB 1217 as grounds to refuse to renew a lease?

Washington’s eviction and non-renewal laws are separate from HB 1217. You cannot use the rent cap as a pretext for retaliation. RCW 59.18.240 prohibits retaliatory actions (including non-renewal) within 6 months of a tenant asserting a legal right or filing a complaint. If a tenant complains about your rent increase, you cannot immediately refuse renewal. However, you can choose not to renew a lease for legitimate, non-retaliatory reasons.

Integration with LeaseBase Rent Payment Tools

Managing compliance with HB 1217 involves coordinating lease renewals, documenting calculations, sending notices, and tracking tenant payments. This is where many self-managing landlords stumble—they miss the 90-day deadline or lose proof of notice.

LeaseBase’s rent payment system integrates with compliance tracking, so you can set a new rent amount in the platform, generate a compliant notice, and electronically deliver it to the tenant—all while maintaining an audit trail.

Our lease operations module sends calendar alerts 90 days before renewal, so you never miss a deadline. And compliance automation crosschecks your rent increase against the current CPI limit, flagging any discrepancies before you finalize the notice.

For landlords managing 2–75 units, compliance gaps compound quickly. A missed deadline on one renewal creates liability; mistakes on multiple renewals create exposure across your portfolio. Platforms designed for self-managing landlords close these gaps without the cost of a property manager ($800+/month).

State Resources and Official Guidance

For the most current information on HB 1217, visit:

• Washington Department of Housing and Community Development (DHCD) — deptofhcd.wa.gov — Official rent increase limit notices published annually by December 1
• Washington State Legislature — RCW 59.18.140 — The full text of the statute
• Washington State Bar Association — Referrals for attorneys specializing in landlord-tenant law
• U.S. Bureau of Labor Statistics — CPI-U data for Seattle-Tacoma-Bellevue (bls.gov)

Do not rely on news articles or third-party summaries for rent increase calculations. The DHCD’s official notice is the legal standard.

Bottom Line: Compliance Is Non-Negotiable

Washington’s HB 1217 rent cap is one of the strictest in the nation. Violations expose you to treble damages, attorney fees, and court costs—penalties that dwarf any rent increase you might have collected illegally. For self-managing landlords, the compliance burden is manageable if you follow the formula, send proper notice, and document everything.

The 90-day notice requirement is the most frequently missed deadline. Mark your calendar now for every lease renewal. Calculate the cap before finalizing your rent. Send certified notice. Keep copies.

Tools like portfolio management platforms that automate deadline tracking and notice generation are worth the investment. The cost of a compliance mishap far exceeds the cost of prevention.

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Disclaimer

This article is for informational purposes only and does not constitute legal advice. Consult a qualified attorney licensed to practice in Washington for guidance specific to your situation. Rent increase calculations and compliance with RCW 59.18.140 involve fact-specific analysis. This article provides general guidance; individual circumstances may vary. The LeaseBase team is not a law firm and does not provide legal services.