Prepare the application
Complete the county’s application, commonly Form BOE-305-AH, and submit it during the applicable filing period.
What is an assessment appeal?
An assessment appeal is the formal process a property owner uses to challenge a county assessor’s assessed value when it may not reflect the property’s taxable value under California law.
Why it matters
The assessed value is used to calculate your property taxes.
Deadlines vary
Filing periods depend on your county and the type of assessment.
Evidence helps
Comparable sales, records, photos, and appraisals can support your position.
WHEN TO CONSIDER ONE
Common reasons owners appeal
- The assessed value appears higher than the property’s market value.
- The property description contains errors, such as incorrect square footage or features.
- The assessment may not reflect Proposition 13, Proposition 8, or applicable new-construction rules.
THE PROCESS
Confirm details with your countyWhat happens from filing to decision?
Gather evidence
Organize comparable sales, appraisals, photographs, property records, and other information that supports your opinion of value.
Attend the review
An Assessment Appeals Board or hearing officer may review the evidence presented by you and the Assessor’s Office.
Receive a decision
The board or officer makes the decision. If the value is reduced, your taxes may decrease and a refund may be possible.
TIMING MATTERS
Check your county’s filing window
Annual filing periods are commonly July 2 through September 15, while some counties, including Los Angeles, may use July 2 through November 30. Supplemental and escape assessments can have different deadlines, often tied to the notice date.
These dates are general guidance, not legal advice. Verify the current deadline and forms with your county.
Start with the facts behind your assessment.
Assessify organizes property information, comparable data, and calculations into a report that can help you prepare for the appeal process.
Explore the 7-step method