In California, a landlord must give at least 90 days’ written notice before a rent increase that raises the rent more than 10% above the lowest amount charged during the previous 12 months. This 90-day rent increase notice rule is set by California Civil Code Section 827 and applies to month-to-month and other periodic residential tenancies statewide.1California Legislative Information. California Civil Code 827 – Change in Terms of Lease Smaller increases require only 30 days’ notice.
When the 90-Day Notice Applies
The threshold is cumulative over 12 months, not per increase. Add together every rent increase the landlord has imposed during the prior 12 months. If the proposed new increase would push that total above 10% of the rent charged at any point in that window, 90 days’ written notice is required.1California Legislative Information. California Civil Code 827 – Change in Terms of Lease
A worked example: a 5% increase in March followed by a 6% increase in September totals 11% within the same 12-month window. The September increase triggers the 90-day rule, even though neither raise alone crosses 10%. Splitting a large increase into smaller ones does not avoid the longer notice period if they fall inside the same 12 months.
If the cumulative 12-month increase stays at 10% or below, the landlord needs to give only 30 days’ written notice.
How the Notice Must Be Delivered
Section 827 allows two delivery methods, and the choice affects how many days you actually get.
- Personal delivery. The notice is handed directly to the tenant, and the notice period begins that day.
- Mail through the U.S. Postal Service, following Code of Civil Procedure Section 1013.
When a landlord uses the mail, California law adds extra calendar days to the notice period. If both the mailing address and the tenant’s address are inside California, five extra days are added. If either address is elsewhere in the United States, the extension is 10 days. If either is outside the country, the extension is 20 days.2California Legislative Information. California Code of Civil Procedure 1013
So a 90-day notice mailed within California is effectively a 95-day notice, and a mailed 30-day notice is effectively 35 days. Any tenant counting days on a rent increase notice should first check how the notice arrived.
What Happens If the Notice Falls Short
A rent increase notice that is even one day short of the required period is void. The tenant owes only the old rent, and the landlord cannot treat nonpayment of the increase as grounds for eviction. To impose the raise, the landlord must start the notice period over.
The problem can grow over time. If a landlord imposed a 12% increase on only 60 days’ notice, that increase was never legally established. Every later increase built on top of it may also be defective, because each one assumes a base rent that was never valid. A tenant challenging the situation later could seek the return of rent collected above the last legally noticed amount.
Why the 90-Day Rule Rarely Applies to AB 1482 Properties
The Tenant Protection Act of 2019 (AB 1482) caps annual rent increases for most residential properties at 5% plus the local Consumer Price Index, or 10% total, whichever is lower.3California Legislative Information. AB 1482 Tenant Protection Act of 2019 Because the cap itself blocks increases above 10%, a covered landlord raising rent by the maximum permitted amount only needs to give 30 days’ notice.
The 90-day rule matters most for properties that fall outside the AB 1482 cap, where increases above 10% are legally possible. Those exempt categories include:
- Housing that received its certificate of occupancy within the previous 15 years. The 15-year window rolls forward each year.4California Legislative Information. California Civil Code 1947.12
- Single-family homes and condominiums, but only if the owner is not a corporation, REIT, or LLC with a corporate member, and the landlord has given the tenant a specific written notice of exemption. Both conditions must be met; without the written notice, the property is treated as covered.4California Legislative Information. California Civil Code 1947.12
- Duplexes where the owner continuously occupies one of the two units.
- Deed-restricted affordable housing for low- or moderate-income residents.4California Legislative Information. California Civil Code 1947.12
- Housing already subject to a local rent ordinance that caps increases below the AB 1482 level.
If you rent one of these exempt property types, an increase above 10% is legal and the 90-day notice requirement is the main protection you have on timing.
The Affordable Housing Recertification Exception
One narrow exception cuts the notice period back to 30 days even when the increase exceeds 10%. When a rent adjustment in affordable housing results from a change in the tenant’s income or household composition, as determined by a recertification required by law or regulation, the landlord only needs to provide 30 days’ notice.1California Legislative Information. California Civil Code 827 – Change in Terms of Lease The exception applies only to rent changes driven by the recertification itself. Any other rent increase in affordable housing still follows the standard 30-day or 90-day rule based on size.
Local Ordinances Can Require Longer Notice
Section 827 sets a floor. Cities with rent stabilization ordinances can require longer notice periods, and when a local rule gives the tenant more time, the local rule controls. Tenants in San Francisco, Los Angeles, Oakland, Berkeley, and other rent-controlled jurisdictions should check with the local rent board in addition to the statewide requirement. Some local ordinances also restrict which units can receive increases at all or require the landlord to petition before certain increases can take effect.
What to Do If You Receive a Notice
Check three things before you accept the new amount. First, add up every rent increase over the last 12 months, including the new one, and see whether the total exceeds 10%. Second, look at how the notice was delivered; if it came by mail, add the appropriate 5, 10, or 20 days to the notice period stated on the document. Third, check whether your city has its own rent ordinance with a longer notice rule. If the notice is short on any of these, the increase is not yet enforceable, and rent stays at the prior amount until a proper notice is served.