Assessment Ratio
100% (Prop 13)
Appeal Deadline
Jul 2 - Nov 30, 2026
Official Form
BOE-305-AH
Risk of Increase
No
How Assessment Works in California
Under Proposition 13, California properties are assessed at their purchase price (base year value) plus a maximum 2% annual increase. Your assessed value can only be reduced if the current market value falls below your factored base year value. This means protests are most effective during market downturns.
How to File in California
File with your county Assessment Appeals Board by mail or in person. Some counties accept online filings. The filing window is July 2 through November 30 (or September 15 in some counties).
Step-by-Step
California Appeal Process
Review your annual assessment notice (mailed in July) showing your property's assessed value.
Compare your assessed value to current market conditions. If market values have declined below your factored base year value, you have a "decline in value" claim.
File Form BOE-305-AH (Assessment Appeal Application) with your county clerk of the Assessment Appeals Board.
Gather evidence: recent comparable sales, a professional appraisal, or market data showing decline.
Attend the hearing before the Assessment Appeals Board and present your evidence.
The board will issue a decision. If granted, your assessed value is reduced, and you receive a tax refund for any overpayment.
FAQ
California Property Tax Appeal Questions
How does Proposition 13 affect my appeal?
Prop 13 caps your assessed value increase to 2% per year from your purchase price. You can only appeal if the current market value is lower than your factored base year value (purchase price plus accumulated 2% increases). During market downturns, this creates significant savings opportunities.
What is a "decline in value" claim?
A decline in value (Prop 8) claim argues that your property's current market value has fallen below its Prop 13 factored base year value. If granted, your assessment is temporarily reduced. When the market recovers, the assessor can restore the value up to the Prop 13 limit.
Can my California assessment go up if I appeal?
No. The Assessment Appeals Board cannot raise your assessment above the value on the current roll. The worst outcome is that your value stays the same.
What is the effective property tax rate in California?
California property tax rates vary by county, municipality, and school district, but the effective rate (annual tax paid divided by market value) typically ranges from about 0.5% to 2.5%. Because California assesses property at 100% (Prop 13) of market value, your actual tax bill depends on both the assessed value and the local millage or mill levy applied on top of it. If your assessed value is higher than comparable sales support, filing a appeal is one of the only ways to reduce your effective rate without waiting for a reassessment.
How long does a property tax appeal take in California?
Most California appeals take between 6 weeks and 6 months from filing to final decision. After you file BOE-305-AH, the assessor or review board schedules a hearing — typically within 30 to 90 days — and issues a written decision shortly after. Cases that settle informally resolve faster, while cases that advance to a formal hearing or court appeal can take several additional months. ProtestMax prepares your full evidence packet in minutes so you can file immediately and start the clock.
Can I appeal my property taxes every year in California?
Yes. In California, homeowners generally have the right to appeal their property tax assessment every year, as long as you file by the Jul 2 - Nov 30, 2026 deadline. Even if you won a reduction last year, your assessor can revalue your property the following year, and you retain the right to challenge the new value. Annual appeals are especially important during years when market values are flat or falling but assessments keep rising.
What evidence is most persuasive in California hearings?
The strongest evidence in a California appeal hearing is recent comparable sales — homes similar to yours in size, age, condition, and location that sold for less than your assessed value within the last 6 to 12 months. Equity comparisons (similar homes assessed for less than yours) are also highly persuasive. Photos of deferred maintenance, structural issues, or negative location factors (busy roads, flood zones, power lines) strengthen your case further. ProtestMax assembles all of this evidence into a hearing-ready packet tailored to California's rules.