California has one of the most homeowner-friendly property tax systems in the country — thanks to Proposition 13 — but that doesn’t mean your assessment is always correct. If your property’s current market value has dropped below its assessed value, you have the right to appeal. Here’s exactly how to do it.
How California Property Taxes Work (Prop 13 Explained)
Under Proposition 13 (passed in 1978), your assessed value is set when you purchase the property and can only increase by a maximum of 2% per year, regardless of what the market does. This is your “base year value.”
The current tax rate is capped at 1% of assessed value, plus local voter-approved bonds and assessments — which typically bring the effective rate to 1.1–1.3% depending on your county.
The catch: if you bought at the peak of the market and values have since dropped, your assessed value may be higher than what your property would sell for today. That’s when you appeal.
When You Can Appeal in California
California offers two types of appeals:
- Regular (Prop 8) Appeal: Filed when your property’s current market value has temporarily fallen below its Prop 13 base year value. This is the most common appeal for homeowners who bought at a market peak.
- Base Year Value Appeal: Filed within 4 years of a purchase or new construction event. You’re arguing that the assessed value set at the time of purchase was incorrect.
Filing Deadlines — Don’t Miss These
The filing window in California is July 2 through November 30 each year for most counties. Some counties have slightly different deadlines — check with your county assessor’s office to confirm yours.
Missing the deadline means waiting an entire year to appeal. Mark your calendar and set a reminder for early October so you have time to gather your evidence before the window closes.
Step-by-Step: How to File a California Property Tax Appeal
Step 1: Check Your Assessment Notice
Your county assessor mails an assessment notice each year, usually in the spring. It shows your land value, improvement value, and total assessed value. Compare this number to what you believe your property would sell for today.
Step 2: Gather Comparable Sales
The strongest evidence in a California appeal is recent sales of similar properties in your neighborhood — ideally within the last 6–12 months, similar square footage, lot size, age, and condition. Zillow, Redfin, and your county assessor’s public records are all valid sources.
Step 3: File the Application
Download and complete the Application for Changed Assessment (form BOE-305-AH) from your county assessor or the California State Board of Equalization website. File it with your county Assessment Appeals Board before November 30.
Step 4: Prepare for the Hearing
You’ll be scheduled for a hearing before the Assessment Appeals Board — typically 3–18 months after filing. Bring printed copies of your comparable sales, any appraisals, photos of property condition issues, and your completed evidence worksheet.
Step 5: Present Your Case
At the hearing, you’ll present your evidence first. Keep it factual and concise: “My property is assessed at $X. Based on these three comparable sales, the current market value is $Y.” The assessor’s representative will respond. The board then deliberates and issues a decision — sometimes the same day, sometimes by mail weeks later.
Key California Counties and Their Appeal Offices
- Los Angeles County: lacountyassessor.com — largest county in the state, heavy backlog, expect long wait times
- Orange County: assessor.ocgov.com — generally efficient, hearings scheduled within 6–9 months
- San Diego County: sdarcc.com — Assessment Appeals Board handles scheduling
- Santa Clara County: sccassessor.org — tech boom valuations make this county especially worth appealing in down markets
- Alameda County: acgov.org/assessor — covers Oakland and Berkeley
What Happens if You Win
If the board lowers your assessed value, you’ll receive a refund of any overpaid taxes for the current year, and your assessment will reflect the corrected value going forward. Under Prop 13, the new lower value becomes your new base that can grow at 2%/year from that point.
What Happens if You Lose
If the board rules in favor of the assessor, you can request reconsideration or file an appeal in Superior Court — though court appeals are expensive and rarely worth it for residential properties. You can file again the following year if market conditions continue to support a lower value.
More State Appeal Guides
- California Property Tax Appeal Guide
- Texas Property Tax Protest Guide
- Florida Property Tax Appeal Guide
- New York Property Tax Appeal Guide
- Illinois Property Tax Appeal Guide
See the Complete Appeal Process
Our step-by-step guide covers evidence gathering, hearing preparation, and what to say to the board — for every state, not just California.
Read the Full Appeal Guide →