California caps most annual rent increases at 5% plus regional inflation, or 10%, whichever is lower (Civil Code 1947.12). Pick your county and the date the increase takes effect, and this applies the published cap for that period.
Use the lowest rent you were charged in the 12 months before the increase — that is the base the statute measures from.
Leave blank to use today’s date. The cap changes every August 1.
The caps this calculator uses
| Area (counties) | Aug 1, 2025 – Jul 31, 2026 | Aug 1, 2026 – Jul 31, 2027 |
|---|---|---|
| Los Angeles and Orange | 8.0% | 8.7% |
| San Francisco, Alameda, Contra Costa, Marin, San Mateo | 6.3% | 8.8% |
| San Diego | 8.8% | 8.2% |
| Riverside and San Bernardino | 7.5% | 8.1% |
| All other counties (including Santa Clara, Sacramento, Ventura and Fresno) | 7.7% | 8.6% |
For a full explanation of these numbers, with worked examples, see how much a landlord can raise rent in California in 2026.
How this tool was built: methodology and sources
The formula is written into statute. Civil Code section 1947.12 limits the increase over any 12 months to “5 percent plus the percentage change in the cost of living, or 10 percent, whichever is lower”, measured from the lowest gross rent charged in the prior 12 months, and in no more than two increments.
Where the inflation figures come from
Section 1947.12(g) names the counties itself. Los Angeles and Orange use the U.S. Bureau of Labor Statistics index for Los Angeles-Long Beach-Anaheim; Riverside and San Bernardino use Riverside-San Bernardino-Ontario; San Diego uses San Diego-Carlsbad; San Francisco, Alameda, Contra Costa, Marin and San Mateo use San Francisco-Oakland-Hayward. Every other county — Santa Clara included — uses the California Consumer Price Index published by the Department of Industrial Relations.
Increases taking effect on or after August 1 use the April-to-April change for that year; where an area has no April figure (San Diego and Riverside-San Bernardino publish in odd months), the March-to-March change is used. The change is rounded to the nearest tenth of a percent. We computed every figure from the BLS and DIR data and checked each one against the Attorney General’s published chart; all ten match.
The cap may not apply to you at all
Section 1947.12 exempts several categories, including deed-restricted affordable housing, dormitories, housing with a certificate of occupancy issued within the previous 15 years (a rolling window), single-family homes and condominiums where the owner is not a corporation, REIT or corporate-member LLC and the required written notice was given, and owner-occupied duplexes. See is my rental exempt? Units under a local rent control ordinance with a lower cap follow the local rule instead — see the guides for Los Angeles, San Francisco, Oakland, Berkeley, San Jose and Santa Monica.
Notice and expiry
An increase of 10% or less needs 30 days’ written notice; more than 10% needs 90 days (Civil Code 827) — see rent increase notice rules. Section 1947.12 is repealed on January 1, 2030 unless the Legislature acts; see what happens when AB 1482 expires. Figures verified 28 September 2026.
This is not legal advice. It calculates the statewide statutory cap only, and cannot tell you whether your specific unit is exempt or covered by a stricter local ordinance.