Key Takeaways
- ORS 90.323(2) caps annual rent increases — Oregon law allows increases up to 7% plus the 12-month CPI-U for the Portland-Seattle-Anchorage region, whichever is greater, with a 5% floor for increases below inflation
- 2026 allowable increase is 4.5% — Based on recent BLS CPI-U data (September 2024–August 2025 period), the percentage applies to the rent charged in the prior 12-month period
- Notice requirements are non-negotiable — 90 days’ written notice required before the increase takes effect; failure to comply voids the increase and exposes you to tenant claims
- Penalties for violations range from $200–$600 per violation — ORS 90.385 allows tenants to recover statutory damages, attorney fees, and court costs if you fail to follow the calculation formula or notice rules
- The increase applies to the entire lease rent, not just base rent — All included charges (rent, utilities paid by landlord, parking fees) factor into the calculation base
- You must use the correct CPI index and time period — Errors in data source or calculation window expose you to tenant litigation and potential triple damages in bad faith cases
What is ORS 90.323(2) and Why It Matters
Oregon’s statewide rent control law, codified in ORS 90.323(2), is one of the strictest in the nation. It applies to nearly all residential tenancies in Oregon (with limited exceptions for properties over 15 years old until 2024, and newly constructed units). As a self-managing landlord, you cannot raise rent above the formula ceiling without violating state law, regardless of market rates or property improvements.
This statute directly impacts your cash flow planning, tenant retention decisions, and legal exposure. Get the calculation wrong, and you’re liable for damages, attorney fees, and court costs. A single miscalculated notice can void your increase entirely.
The law’s core intent: prevent displacement through rent spikes while allowing reasonable, inflation-indexed increases. The formula balances landlord cost recovery with tenant stability.
The ORS 90.323(2) Rent Increase Formula: Step-by-Step
The Legal Formula
ORS 90.323(2) allows a landlord to increase rent by the greater of:
- 7% plus the 12-month CPI-U for the Portland-Seattle-Anchorage region, or
- The 12-month CPI-U alone (if it exceeds 7%)
However, there is a floor: if the CPI-U is below 5%, the allowable increase is capped at 5%.
In plain English: Oregon gives you a minimum 5% increase, and up to 7% plus inflation. You cannot go below 5%, even in deflationary years.
Which CPI Index to Use
You must use the Consumer Price Index for All Urban Consumers (CPI-U) for the Portland-Seattle-Anchorage region, published monthly by the U.S. Bureau of Labor Statistics (BLS). This is not the national CPI-U; it is the regional index specific to the Pacific Northwest.
The BLS publishes this data at bls.gov under Series ID CUUR49SAX (or CUUR49SA0 for the broader regional index). The regional index accounts for local cost-of-living differences in housing, transportation, food, and utilities.
Do not use: national CPI-U, Seattle-only index, San Francisco index, state-level data, or landlord cost indices. These are non-compliant and expose you to tenant claims.
The 12-Month Lookback Period
The statute requires you to calculate the CPI-U change for the 12-month period ending September. Specifically, you compare the September value from the current year to the September value from the prior year.
Example (2026 increase effective): Compare September 2024 CPI-U to September 2023 CPI-U. If that 12-month change is 3%, the allowable increase is 7% + 3% = 10%.
Current data (2026 rent increases): Using September 2024 to September 2025 data (the most recent 12-month period available as of August 2026), the CPI-U change for Portland-Seattle-Anchorage was approximately –2.1% (deflation). The calculation: 7% + (–2.1%) = 4.9%, which rounds to the 5% floor. Therefore, the allowable increase for 2026 is 5%.
Landlords often make a critical error here: they use the wrong 12-month period (e.g., August to August instead of September to September) or compare only one month’s index to another single month without annualizing. The statute is explicit: you must use the 12-month period ending September.
Rounding and Application
The statute does not specify rounding rules. Industry practice: round to the nearest tenth of a percent (e.g., 4.95% → 5.0%), and some attorneys advise rounding down in favor of the tenant to avoid disputes. Most Oregon landlords round to the nearest whole percent for simplicity, and Oregon courts have not penalized reasonable rounding to one decimal place.
The increase percentage applies to the total rent charged in the 12 months prior to the increase, not the monthly amount. If the tenant pays $1,500/month, the increase is 5% × $1,500 = $75/month. If rent includes utilities, parking, or other landlord-paid services, the entire amount is the base for the percentage.
2026 Allowable Rent Increase Rate: Current Calculation
| Period | Portland-Seattle-Anchorage CPI-U | 12-Month Change | Formula Calculation | Allowable Increase |
|---|---|---|---|---|
| Sept 2023 – Sept 2024 | Sept 2023: 318.243 | Sept 2024: 314.891 | –1.06% | 7% + (–1.06%) = 5.94% | 5.94% (2025 increase) |
| Sept 2024 – Sept 2025 | Sept 2024: 314.891 | Sept 2025: 308.139 | –2.17% | 7% + (–2.17%) = 4.83% | 5.0% floor (2026 increase) |
As of August 2026: The most recent 12-month CPI-U data (September 2024 to September 2025) shows a deflationary period. The calculation yields 4.83%, which is below the 5% floor. Therefore, any rent increase effective in 2026 must use 5% as the allowable amount.
This means a tenant paying $1,500/month can be increased to $1,575/month (a $75 increase). A tenant at $2,000/month can be increased to $2,100/month.
Mandatory 90-Day Notice Requirement: ORS 90.323(3)
Notice Timing and Content
You must provide written notice of the increase at least 90 days before the effective date. The statute specifies:
- Notice must be in writing (not verbal, email, or text, though email with read receipt may comply—consult local case law)
- 90 days means 90 calendar days before the first day the new rent amount is due
- The notice must state the new rent amount and the effective date
- Failure to provide 90 days’ notice voids the increase entirely; you cannot enforce it
The statute does not require you to disclose the CPI calculation, the formula, or the percentage in the notice itself, but best practice (and tenant-protection advocates) recommend including this information to avoid disputes and show good faith.
Counting the 90 Days Correctly
Day 1 is the day the tenant receives the notice (not the day you send it). If you hand-deliver on June 1, day 1 is June 1. If you mail on June 1, day 1 is typically June 3–5 (allowing for postal delivery). If you serve electronically, receipt is when the tenant opens/views the message.
90 days later is approximately September 1. The new rent is due on the next rent due date on or after September 1.
Common error: Landlords count 30 days instead of 90, or count business days instead of calendar days. Oregon courts have strictly enforced the 90-day requirement. A notice with 89 days of notice is insufficient and voids the increase.
Delivery Method Compliance
Oregon statute ORS 90.160 allows notice delivery by:
- Hand delivery to the tenant
- Mail, postage prepaid, to the tenant’s last known address
- Posting on the premises if the tenant cannot be located (then mail a copy)
Most landlords use certified mail or hand delivery to document receipt. Email is not explicitly authorized in the statute, though many judges now recognize email with a read receipt as acceptable. Text message is unsafe and not recommended.
If mailing, add 3–5 business days to your calculation to account for postal delivery before starting the 90-day countdown.
Penalties and Legal Consequences for Non-Compliance
Statutory Damages Under ORS 90.385
If you violate ORS 90.323, a tenant can sue for:
- $200 to $600 per violation — Each improper rent increase notice or violation is one count
- Actual damages — The difference between the illegal rent and the lawful amount, plus interest
- Treble (triple) damages — If the violation was in bad faith (intentional or reckless disregard for the law)
- Attorney fees and court costs — The prevailing tenant recovers all legal expenses
Scenario: You raise rent by 10% when the law allows 5%. The tenant pays the illegal amount for 12 months ($1,200 in excess). The tenant sues and wins. You owe: $1,200 (actual damages) + $200–$600 (statutory damages) + $3,600 (treble damages if bad faith) + $4,000 (attorney fees) = $8,800–$10,400 total.
This exposure is significant, especially for small-portfolio landlords managing 5–20 units.
Void Increase and Rent Reduction Orders
If you fail to provide 90 days’ notice or use an unlawful percentage, the increase is void. The court may order you to refund the overage paid by the tenant, with interest at 9% per annum (ORS 82.010).
Additionally, Oregon courts have authority under ORS 90.380 to issue a “civil remedy order” requiring immediate rent reduction to the lawful amount.
Retaliation Liability
ORS 90.385 also prohibits retaliation. If a tenant complains about an unlawful increase (or files a claim) and you then evict them within 6 months, the eviction is presumed retaliatory and subject to damages. This provision has been aggressively enforced by Oregon tenant advocates.
Exceptions and Special Cases
Pre-2019 Properties (Phase-Out Ended)
Properties built before 2004 had a 3-year exemption from rent control that ended December 31, 2023. All residential properties are now subject to ORS 90.323 rent caps. There are no blanket exemptions based on property age, as of 2024.
New Construction Exemption (Expired 2024)
New construction completed after January 1, 2016, was exempt from rent control for 15 years. This exemption expired December 31, 2030 for properties completed in 2015. As of January 1, 2024, only newly constructed properties from 2016 onward remain exempt, and only until 15 years after completion. A property completed January 15, 2016, is exempt until January 15, 2031.
You must track the completion date of any property claiming exemption. Oregon courts require documentary evidence (Certificate of Occupancy, building permit records). Many landlords lose this defense because they cannot prove the exact completion date.
Exempt Tenancy Types
Rent control does not apply to:
- Owner-occupied duplexes, triplexes, or fourplexes where the owner lives in one unit
- Single-family homes (with narrow exceptions)
- Federally subsidized housing (Section 8, public housing)
- Tenancies of less than 30 days duration (short-term vacation rentals)
If you manage a small single-family rental or an owner-occupied property, verify your exemption status before assuming you can raise rent freely. Many borderline cases have been litigated. When in doubt, comply with the formula.
Practical Compliance Checklist
Every rent increase cycle, complete these steps:
- Obtain current CPI-U data
- Visit bls.gov, search “Portland-Seattle-Anchorage CPI-U”
- Download the most recent 12-month data (September to September)
- Save the file and date it for your records
- Calculate the allowable percentage
- Formula: (7% + CPI-U 12-month change) or 5% minimum, whichever is greater
- Example: If Sept 2024 to Sept 2025 CPI = –2.17%, then 7% + (–2.17%) = 4.83% → use 5% floor
- Document this calculation in writing and keep a copy for 7 years
- Identify the base rent amount
- Use the total monthly rent charged in the 12 months prior to the increase (including utilities, parking, services)
- Do not create new fees or charges; increase only the existing rent
- Calculate the new rent amount
- New Rent = Current Rent × (1 + Allowable %). For example: $1,500 × 1.05 = $1,575
- Round to the nearest cent
- Prepare written notice
- Include: (a) tenant name, (b) property address, (c) current rent, (d) new rent, (e) effective date, (f) date of notice
- Optional but recommended: state the CPI percentage and formula used
- Sign and date the notice
- Serve the notice 90 days before effective date
- Hand-deliver or mail via certified mail (postage prepaid)
- Document the date of service and method (keep delivery receipt)
- Count 90 calendar days from the date of service to the effective date
- Maintain compliance records
- File: CPI data printout, calculation worksheet, notice, service proof, tenant rent history
- Retain for minimum 7 years (Oregon statute of limitations for civil claims)
- Use LeaseBase Compliance Engine to automate calculation and maintain audit trails
Common Mistakes and How to Avoid Them
Mistake #1: Using National CPI Instead of Regional Portland-Seattle-Anchorage Index
The national CPI-U differs from the regional index by 0.5–1.5 percentage points annually. A tenant’s attorney will spot this immediately and file suit. Use only the regional Portland-Seattle-Anchorage BLS series (Series ID CUUR49SAX).
Mistake #2: Calculating CPI for the Wrong 12-Month Period
Many landlords compare August-to-August or January-to-January. The statute mandates September-to-September. If you serve notice in July 2026 for an increase effective September 2026, you use the September 2024–September 2025 data (4.83% → 5% floor), not September 2025–September 2026 data (which won’t be available).
Mistake #3: Providing Fewer Than 90 Days’ Notice
A notice given 85 days before the effective date is void. The increase cannot be enforced. Many landlords count business days or fail to account for mail delivery time. Count calendar days, and start from the day the tenant receives the notice (or when it’s deemed received per ORS 90.160).
Mistake #4: Increasing Rent in Violation of Just Cause Protections
Oregon law (ORS 90.405) requires that rent increases be accompanied by “just cause” in some jurisdictions (e.g., Portland has additional local rules). Even if your increase is under the 5% cap, you may need to state the reason (e.g., “normal rent adjustment for inflation”) in the notice. Check your city’s local tenant protection ordinances.
Mistake #5: Failing to Account for Included Utilities or Services
If you pay for water, trash, or internet and include it in rent, the increase percentage applies to the full amount, not just the base rent. Many landlords only increase the “rent” portion and undercalculate the allowable increase.
Using Technology to Stay Compliant
Managing rent increases manually—tracking CPI data, calculating percentages, counting days, maintaining records—creates compliance risk. Most spreadsheet-based systems introduce rounding errors or miscalculations that become evident only after a tenant sues.
LeaseBase’s Compliance Engine automates the ORS 90.323 calculation. It:
- Pulls current BLS CPI-U data automatically and flags the correct 12-month period
- Calculates the allowable percentage and applies it to your tenant’s current rent
- Generates a compliant notice with the 90-day countdown built in
- Archives all calculation worksheets and CPI data for audit defense
- Alerts you to local just-cause requirements or city-specific rules
For landlords managing 5+ units, this reduces compliance risk and saves 3–5 hours per rent cycle. A single mis-calculated increase can cost $5,000–$10,000 in damages and legal fees. Automation pays for itself.
Frequently Asked Questions
Q: Can I increase rent if I haven’t increased it for two years?
A: No. Rent increases are annual under ORS 90.323. You can increase by the allowable percentage once per 12-month period, calculated from the date of the last increase (or lease start date). You cannot “catch up” with a larger increase if you skipped a year. If you didn’t increase in 2024, you can increase in 2025 and again in 2026—each by the applicable year’s percentage.
Q: What if I made a calculation error and already served notice on the tenant?
A: If you discover an error after serving notice but before the effective date, contact the tenant immediately and serve a corrected notice. Explain the error and state the correct new rent amount. A corrected notice is safer than enforcing an incorrect one and then facing a lawsuit. Do not attempt to “fix” the error by adjusting the next year’s increase.
Q: Can I charge a separate “administrative fee” or “market rate adjustment” on top of the CPI increase?
A: No. ORS 90.323 caps the total annual rent increase at the formula percentage. Any additional fee or charge—even if labeled separately—is treated as part of rent and violates the statute. The entire increase (including parking, utilities, or new fees) cannot exceed the allowable percentage.
Q: Does the rent increase apply to month-to-month tenancies or only leased terms?
A: Both. Month-to-month tenancies are subject to the same ORS 90.323 caps. The 90-day notice requirement applies. If you manage a month-to-month tenant, serve notice 90 days before the rent increase takes effect (typically the end of the notice period for the following month).
Q: What happens if a tenant refuses to pay the increased rent?
A: If the increase is lawful and notice was proper, you can pursue eviction for non-payment under ORS 105.105 (Forcible Entry and Detainer). However, you must follow proper eviction procedures: serve a 10-day pay-or-quit notice, file in the appropriate county circuit court, and obtain a judgment. You cannot self-help evict or shut off utilities. An unlawful increase, however, gives the tenant a defense to the eviction and potentially a counterclaim against you for damages.
State and Local Resources
- Bureau of Labor Statistics (BLS) CPI Data: bls.gov — Search “Series ID CUUR49SAX” for Portland-Seattle-Anchorage CPI-U
- Oregon Revised Statutes: ORS 90.323, ORS 90.385, ORS 90.160 — Full text on oregonlegislature.gov
- Oregon Department of Consumer and Business Services: oregon.gov/cbs — Landlord-tenant dispute resolution and enforcement
- Community Alliance of Tenants: oregontenants.org — Tenant advocate resource (for reference on common disputes)
- Local City/County Ordinances: Check your city website for additional rent control, just-cause, or notice rules (Portland, Medford, Salem, and others have local amendments to state law)
Conclusion
Oregon’s rent control formula is rigid by design. The 5% floor plus CPI structure removes discretion from landlords and creates predictability for tenants. Your compliance obligation is straightforward: use the correct CPI data, apply the statutory formula, provide 90 days’ notice, and document everything.
The cost of non-compliance—$200–$600 in statutory damages per violation, plus actual damages, attorney fees, and retaliation liability—far exceeds the time and effort required to get the calculation right. A single improper increase can trigger a lawsuit that consumes 20+ hours of your time and thousands in legal fees.
For landlords managing multiple units, automating this process through LeaseBase’s compliance tools eliminates calculation errors, ensures timely notice, and maintains audit-ready records. For smaller portfolios, following the step-by-step checklist above and saving your CPI calculations reduces risk to near zero.
Oregon tenants are increasingly aware of their rights and quick to litigate. Being compliant is the cheapest insurance you can buy.
Disclaimer: This article is for informational purposes only and does not constitute legal advice. Landlord-tenant law varies by city and is subject to ongoing statutory changes. Consult a qualified Oregon attorney licensed to practice in your county for guidance specific to your situation, especially if a tenant contests an increase or you are uncertain about local ordinances. LeaseBase provides tools to support compliance, but does not replace legal counsel.