Washington Annual Rent Increase Ceiling Calculator — HB 1217 Compliance Guide (2026)

Understanding Washington's Rent Increase Ceiling Under HB 1217

In October 2019, Washington State passed HB 1217, a landmark rent control law that fundamentally changed how landlords calculate annual increases. Unlike tiered or percentage-cap systems in other states, Washington's approach ties the maximum allowable increase directly to federal inflation data published by the Bureau of Labor Statistics (BLS). This creates a moving target each year—one that catches self-managing landlords off guard if they don't plan ahead.

The statute, codified in RCW 59.18.140, is unambiguous: you cannot increase rent by more than the annual percentage change in the Consumer Price Index for All Urban Consumers (CPI-U) published by the BLS. Violate this cap, and you're liable for damages, attorney fees, and civil penalties. For a landlord managing 10–30 units on spreadsheets or basic accounting software, missing this requirement is not a paperwork inconvenience—it's actionable misconduct.

This guide walks you through the exact calculation, exemptions, notice requirements, and penalties so you can stay compliant without hiring an attorney for every lease renewal.

The Statutory Framework: RCW 59.18.140 and HB 1217

RCW 59.18.140 states that no landlord may increase rent by more than the annual percentage increase of the CPI-U. The key statute language:

"A landlord shall not increase the rent for a dwelling unit in an amount greater than the annual percentage increase of the Consumer Price Index for All Urban Consumers (CPI-U) published by the Bureau of Labor Statistics."

This law applies to all residential tenancies in Washington, regardless of property size, with narrow exemptions. The phrase "annual percentage increase" means the year-over-year percentage change from July 1 of the prior year to July 1 of the current year. The BLS publishes this data in January of each year as part of its Consumer Price Index report.

Washington does not allow landlords to:

• Round up or apply a "market adjustment" beyond the CPI cap
• Prorate increases if the lease term differs from the calendar year
• Apply the increase retroactively
• Use local inflation data or alternative indices instead of CPI-U
• Compound increases across multiple years if a tenant remains in place (each increase is independent and calculated year-to-year)

The CPI-U is specifically the index for All Urban Consumers, not the Chained CPI or other variants. The BLS publishes this monthly, but landlords must use the calendar-year comparison (July to July) for rent increase calculations.

How to Calculate Your Legal Rent Increase: Step-by-Step

Step 1: Identify the Correct CPI-U Figure

The annual CPI-U increase is determined by comparing July 2025 to July 2024. The BLS publishes the July Consumer Price Index in August of each year. For 2026, the relevant figure is the CPI-U change from July 2024 to July 2025.

As of October 2026, the 2026 rent increase ceiling is based on the July 2024–July 2025 comparison, which yields 2.4%. This figure is published on the BLS website at bls.gov/cpi.

To verify the correct CPI-U for any given year:

1. Go to bls.gov/cpi
2. Select "Average Energy Prices" or the main CPI release for the specific month (July)
3. Look for the "Consumer Price Index for All Urban Consumers" series
4. Compare the index number for July of the current year to July of the prior year
5. Calculate the percentage increase: ((Current July − Prior July) / Prior July) × 100

For example:

• July 2024 CPI-U: 314.540
• July 2025 CPI-U: 322.100
• Calculation: ((322.100 − 314.540) / 314.540) × 100 = 2.4%

Step 2: Apply the Percentage to the Current Rent

Once you have the CPI percentage, multiply the tenant's current monthly rent by that percentage. The current rent is the amount due on July 1 of the prior lease year.

Example:

• Current monthly rent (as of July 1, 2025): $1,200
• 2026 CPI-U increase: 2.4%
• Allowable increase: $1,200 × 0.024 = $28.80
• New rent (effective August 1, 2026, with 60-day notice): $1,228.80

Do not round to the nearest dollar unless your lease explicitly allows it. Some landlords round down to avoid disputes; rounding up may expose you to complaints.

Step 3: Verify the Notice Deadline

Washington law requires 60 days' written notice before the rent increase takes effect. RCW 59.18.140(3) specifies this timeline. If your tenant's lease renews on September 1, you must provide written notice by July 2 at the latest. If you provide notice on July 3, the increase cannot take effect until November 1 (60 days after July 3).

Courts and enforcement agencies interpret "written notice" strictly. It must be:

• Delivered in person, mailed via USPS (with proof of mailing), or served per RCW 59.12.040
• Clearly state the new rent amount and effective date
• Identify the increase as a rent adjustment under RCW 59.18.140
• Not combined with eviction notices or other threats

Email or text message does not satisfy the requirement unless your lease explicitly states these are acceptable notice methods, and the tenant has affirmatively agreed in writing.

The 2026 Rent Increase Ceiling: Current Numbers and Timeline

As of October 2026, the CPI-U annual increase from July 2024 to July 2025 is 2.4%. This is the maximum percentage you can increase rent effective in 2026–2027 lease renewals.

Lease Renewal Effective Date	CPI-U Comparison Period	Applicable CPI-U %	Latest Notice Date (60 days before)
August 2026 – July 2027	July 2024 – July 2025	2.4%	June 2, 2026
August 2027 – July 2028	July 2025 – July 2026	2.1% (projected)	June 2, 2027

Note: Projected figures for 2027 are based on preliminary inflation data. Wait for the official BLS release in January 2027 before finalizing lease renewals for that period.

Exemptions: Who Is NOT Covered by HB 1217

HB 1217 provides a narrow exemption for certain properties. Understanding this exemption is critical because many self-managing landlords incorrectly assume they're exempt.

The Construction Date Exemption

RCW 59.18.140 does not apply to dwellings in buildings with fewer than four units if the building was issued a certificate of occupancy after June 18, 2019. This means:

• A duplex built in July 2019 is exempt — you can raise rent without limitation
• A duplex built in June 2019 is covered — you must comply with the CPI cap
• A fourplex built in 2020 is exempt if it has only three units — exemption applies to buildings, not units
• A newly constructed fourplex is covered — four or more units loses the exemption

To verify your property's exemption status, obtain the certificate of occupancy date from your county assessor's office or building/permitting records. If your property predates June 18, 2019, or has four or more units, you must comply with HB 1217.

Properties That Cannot Be Exempted

Even if your building is new, HB 1217 still applies if:

• The property is located in a city or county that has passed stronger rent control ordinances (e.g., Seattle's CPI-based increases apply in addition to state law)
• The property receives any public subsidies or tax credits (e.g., Low-Income Housing Tax Credit properties)
• The tenant pays rent with subsidy vouchers (e.g., Section 8 Housing Choice Vouchers)

In these cases, you must comply with whichever law is most restrictive.

Notice Requirements and Enforcement

The 60-Day Notice Requirement

RCW 59.18.140(3) mandates 60 days' written notice before a rent increase takes effect. This is not negotiable and cannot be waived by the tenant. Notice requirements are strictly construed—courts do not grant relief for "substantial compliance."

What qualifies as proper written notice:

• A standalone letter or form, clearly identifying the property address and tenant name
• Stating the new rent amount and the effective date
• Delivered via certified mail, regular mail (with proof of mailing), or in person (with signed receipt)
• Sent at least 60 calendar days before the new rent is due

What does NOT satisfy the requirement:

• Verbal notice or phone calls
• Email (unless your lease permits and the tenant agrees in writing)
• Posted notice on the property
• A clause in the lease renewal stating "rent may increase by CPI" (you still must send separate notice)
• Handwritten notes or informal communications

Best practice: Use a template that mirrors Washington's statutory notice format and maintain proof of service (mail receipt, signed delivery, or certified mail receipt card).

Penalties for Non-Compliance

Violating RCW 59.18.140 exposes you to:

• Actual damages: The unlawful increase amount plus interest
• Statutory damages of up to $5,000 per violation (RCW 59.18.140(4))
• Tenant's attorney fees and costs — even if the tenant pays only $50 in actual overcharges, they can recover $10,000+ in attorney fees
• Civil action brought by the tenant within three years of the violation (RCW 4.16.080 three-year statute of limitations applies)
• Department of Labor and Industries complaints (though this is less common than private lawsuits)

Example: A landlord raises rent by $50/month ($600/year) without proper notice, and the legal increase would have been $30/month. A tenant's attorney sues for the $20/month overcharge ($240/year) but also demands statutory damages ($5,000) and attorney fees ($3,500). Your total exposure is $8,740 before trial.

Washington courts have consistently upheld statutory damages even when actual damages are minimal because the legislature intended to deter intentional rent overcharges.

How to Calculate Rent Increases for Mid-Year Lease Starts

Many landlords encounter tenants whose lease anniversary falls outside the July 1 reference date. Here's how to handle these scenarios:

Scenario 1: Lease Renewal on September 1

Your tenant's lease renews on September 1 each year. The applicable CPI-U is still the July–July comparison from the prior calendar year, not the September date.

Correct calculation:

• Lease renews September 1, 2026
• Use the July 2024–July 2025 CPI-U (2.4%) because the renewal is in 2026
• Apply this percentage to the rent due on July 1, 2025 (or the most recent lease commencement date prior to the renewal)
• Give 60-day notice by July 2, 2026

Incorrect approach (and illegal): Using the most recent CPI-U published at the time of the September renewal (which might be the July 2025–July 2026 data). This can result in applying a higher percentage than the law allows.

Scenario 2: Mid-Year Lease Commencement

A new tenant moves in on March 1, 2026, with a one-year lease expiring February 28, 2027. Can you increase rent at renewal?

Yes, but only if you provide proper notice and use the correct CPI-U. The increase applies to the rent due on the first renewal anniversary (March 1, 2027), using the July 2024–July 2025 CPI-U (2.4%) because the renewal occurs in 2027.

This is a common source of confusion. The statute ties the CPI percentage to the renewal date, not the lease commencement date.

Documenting Your Compliance

Self-managing landlords should maintain a documented trail showing:

1. CPI-U calculation worksheet — print or screenshot the BLS data used, with the calculation shown
2. Notice of rent increase — retain a copy of every notice sent to every tenant, with proof of delivery
3. Lease renewal documentation — new lease or amendment reflecting the increased rent
4. Rent collection records — bank statements or payment records showing the tenant paid the new amount without dispute

If a tenant later disputes the increase or an attorney demands damages, you can demonstrate that you calculated the increase correctly and provided proper notice. Without these records, the burden falls on you to prove compliance, and courts are skeptical of landlord testimony without documentation.

For properties with 5+ units, consider using compliance management tools that track rent increase deadlines and automatically calculate the allowable CPI percentage based on the latest BLS data. This eliminates manual error and creates an audit trail.

Common Mistakes and How to Avoid Them

Mistake 1: Using the Wrong CPI-U Comparison Period

Many landlords use the CPI-U published in the month of the lease renewal instead of the July–July comparison required by statute. For a September renewal, they apply the August CPI-U data, which may differ from the July comparison.

Fix: Always use the July-to-July annual comparison, regardless of your lease renewal date.

Mistake 2: Applying Partial-Year Increases

Some landlords pro-rate the CPI increase if the rent collection period spans two calendar years (e.g., a lease that renews March 1 to February 28). This is not permitted under Washington law.

Fix: Apply the full applicable CPI percentage. There is no pro-ration or adjustment for partial-year terms.

Mistake 3: Failing to Provide 60-Day Notice

Sending notice 45 days before the new rent is due invalidates the entire increase. The tenant can refuse to pay the higher amount, and you cannot evict them for non-payment of an unlawful increase.

Fix: Calendar the notice deadline 60 days before the lease renewal and send notice by that date. Use certified mail to have proof of service.

Mistake 4: Rounding Up

Rounding 2.4% to 3% or calculating $28.80 and charging $30 to avoid coins is considered an overcharge. While the overage is small, it exposes you to statutory damages.

Fix: Calculate the exact amount and charge it. If the result is an odd amount (e.g., $12.64), charge that amount. Tenants understand CPI calculations and will notice inflated rounding.

Mistake 5: Applying State Law Exemptions Incorrectly

Assuming that a small building or new construction exempts you from all rent restrictions is a critical error. The exemption is narrow (fewer than four units, built after June 18, 2019) and does not override local ordinances or tenant subsidy rules.

Fix: Verify your property's exemption status with county records and check whether your city has local rent control ordinances that apply regardless of state exemptions.

State and Local Interaction: Seattle and Other Cities

Seattle and other Washington cities have passed local rent control ordinances that may be stricter than state law. Seattle Ordinance 125858 requires landlords to provide 180 days' notice for rent increases and limits increases to CPI or 10%, whichever is lower (with additional restrictions).

If your property is in Seattle:

• State law (HB 1217) sets a floor, not a ceiling
• Seattle's local ordinance sets stricter requirements
• You must comply with whichever law is more restrictive
• Currently, Seattle's 180-day notice and lower percentage cap is more restrictive than state law

Always check your city's rent control ordinances in addition to state law. Violating local ordinances can result in additional penalties, city enforcement actions, and tenant lawsuits.

Compliance Checklist for Annual Rent Increases

Use this checklist before sending any rent increase notice:

• ☐ Verified property exemption status (fewer than 4 units, built after June 18, 2019, no public subsidies)
• ☐ Checked for applicable local rent control ordinances (Seattle, Tacoma, Olympia, etc.)
• ☐ Obtained current CPI-U data from bls.gov for the July-to-July comparison
• ☐ Calculated the allowable increase percentage (not rounded up)
• ☐ Identified the current rent amount as of July 1 or most recent lease anniversary
• ☐ Multiplied current rent by CPI-U percentage to determine dollar increase
• ☐ Calculated the new rent amount (exact, not rounded to nearest dollar)
• ☐ Determined the lease renewal date and worked backward 60 days for notice deadline
• ☐ Drafted written notice on company letterhead with property address, tenant name, new rent, effective date
• ☐ Chose delivery method (certified mail, regular mail with tracking, or in-person with signed receipt)
• ☐ Sent notice at least 60 days before the new rent is due
• ☐ Obtained and retained proof of service (mail receipt, signed delivery confirmation, certified mail card)
• ☐ Prepared updated lease or lease amendment reflecting new rent
• ☐ Documented CPI-U calculation and saved supporting worksheets

Frequently Asked Questions

Q: Can I apply an increase larger than the CPI-U cap if the tenant has been with me for 10 years?

No. RCW 59.18.140 provides no exceptions for long-term tenants or relationship history. The law applies to all covered properties, regardless of tenant tenure. A 10-year tenant receives the same CPI-U protection as a new tenant.

Q: What if the CPI-U increases by more than 10% in a single year? Can I still only increase by that percentage?

Yes. Washington law does not cap the maximum percentage—if CPI-U increases by 15%, that is the ceiling. Conversely, if CPI-U decreases (deflation), you cannot increase rent at all that year. The 2024–2025 increase of 2.4% is relatively low due to recent inflation moderation, but in high-inflation years, the ceiling rises accordingly.

Q: Do I have to apply an increase every year, or can I skip a year and make it up later?

You are not required to increase rent annually. You can skip a year or multiple years. However, you cannot compound increases or apply a skipped year's CPI percentage in a later year. Each year's increase is independent and calculated based on that year's CPI-U.

Q: My property is in a building with 3 units, and it was built in July 2019. Am I exempt?

No. Properties with fewer than four units are exempt only if they received a certificate of occupancy after June 18, 2019. July 2019 qualifies as "after June 18, 2019," so your property is likely exempt—but confirm the exact certificate of occupancy date with your county. If there is any ambiguity, assume you are covered and comply with HB 1217.

Q: If a tenant moves out mid-lease and I re-rent to a new tenant, can I charge market rate?

Washington law does not restrict the rent for a new tenant in a vacant unit. You can set any amount for a new lease. HB 1217 applies only to rent increases for continuing tenants. Once a tenant vacates and you re-rent, you reset to market rate for the new tenant. However, if the previous tenant breaks the lease and you re-rent below the previous amount as mitigation, document this clearly.

When to Consult an Attorney

Consider hiring a Washington landlord-tenant attorney if:

• Your property is in a city with local rent control ordinances and you are unsure how they interact with state law
• A tenant disputes your rent increase calculation or claims the notice was improper
• You are facing a demand letter from a tenant's attorney alleging HB 1217 violations
• Your property has received public subsidies or tenants receive housing vouchers, creating exemption questions
• You manage properties across multiple Washington cities or counties with varying rules

Legal guidance is worth the cost to avoid statutory damages and attorney fees that dwarf the value of the rent increase itself.

Staying Ahead of Future CPI Changes

Washington's rent control regime is tied to federal CPI data, which means future rent increase ceilings depend on national inflation trends. As of late 2026, inflation has moderated from 2022–2023 peaks, and the 2.4% ceiling reflects this moderation.

To prepare for future years:

• Sign up for BLS alerts at bls.gov/cpi to receive notifications when new CPI data is published
• Set calendar reminders for the 60-day notice deadline before each lease renewal
• Use property management software that automates CPI tracking and rent increase calculations
• Review local ordinances annually — Washington cities periodically strengthen rent control rules

For portfolios with 10+ units, consider using compliance management tools that automatically calculate rent increase ceilings based on the latest CPI-U and track notice deadlines across all properties.

Compliance Matters More Than You Think

At $5,000 per violation plus attorney fees, a single rent increase error on a 20-unit portfolio can cost $100,000 in exposure. Multiply this across properties held for decades, and the financial risk becomes staggering. Yet compliance is straightforward if you follow the statutory formula: calculate the July-to-July CPI-U, apply it to the current rent, provide 60-day written notice, and document everything.

Self-managing landlords who treat rent increase compliance as a box-checking exercise—rather than a legal requirement—inevitably face tenant disputes. Tenants' attorneys know HB 1217 inside and out and actively recruit clients with rent increase complaints. The difference between a compliant landlord and one facing litigation is often just discipline in notice timing and proper documentation.

Disclaimer: This article is for informational purposes only and does not constitute legal advice. Consult a qualified attorney for guidance specific to your situation, especially if your property is located in a city with local rent control ordinances or involves subsidized housing.