San Mateo County Property Tax Appeal Guide: How to Lower Your Property Taxes

Homeowners in San Mateo County, California can challenge their property tax assessments if they believe the assessed value is too high. Filing a property tax appeal can save you money and ensure your property taxes reflect your home’s true market value.

Understanding Property Taxes in San Mateo County

Property taxes in San Mateo County are based on the assessed value of your property, which is maintained and updated annually by the County Assessor. You may have grounds for appeal if your home’s assessed value is higher than comparable properties or if there are errors in your property record. Common reasons include:

• Incorrect square footage or property details
• Comparable homes in your neighborhood are valued lower
• Changes in property condition, such as damage or deferred maintenance

Key Deadlines

For the 2026 tax year, the San Mateo County Assessment Appeals Board requires appeals to be filed within specific timelines:

• Regular Appeals: Typically from July 2 to September 15
• Late filings: Only accepted in limited situations, such as supplemental or escape assessments

Missing the deadline usually results in your assessment remaining unchanged for the year.

Steps to File a Property Tax Appeal

Review Your Assessment Notice

Compare your property’s assessed value with recent sales of similar homes in San Mateo County.

Gather Evidence

Include supporting documents:

• Recent appraisals
• Comparable property sales
• Photos of your property or any damage

Submit Your Appeal

File your appeal online or by mail to the San Mateo County Assessment Appeals Board with all supporting evidence.

Attend the Hearing

If the case is not resolved during review, a hearing may be scheduled where you can present your evidence.

Receive the Decision

If approved, your assessed value will be adjusted for the applicable tax year, which may result in a refund or credit.

Tips for Success

• File Early: Early submissions help ensure a complete filing and avoid missed deadlines
• Consider Professional Help: Services like LowPropTax can simplify the process and maximize savings
• Be Organized: Provide clear, thorough evidence to strengthen your case

Challenging your property tax assessment in San Mateo County can significantly reduce your tax burden. By understanding the process, meeting deadlines, and providing strong evidence, homeowners can ensure their property taxes are fair.