San Mateo County · California (CA)

How to Appeal Your Property Tax Assessment in San Mateo County

File an Assessment Appeal Application (BOE-305-AH) with your county Assessment Appeals Board. The 2026 filing window opens July 2 in every county and closes September 15 in 11 counties or November 30 in the other 47, depending on when your assessor mails value notices (source: BOE Letter To Assessors 2026/023).

Filing Deadline

July 2 to November 30

Appeals Body

San Mateo County Assessment Appeals Board

Generate Your San Mateo County Appeal Letter

Answer 3 questions, pick comparable properties, download your San Mateo County Assessment Appeals Board-ready letter. Only pay when you are happy with the result.

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Filing Steps for San Mateo County

1. Gather comps

Find 3-5 comparable properties in San Mateo County assessed lower per square foot than yours. Use the county assessor's public records or property sites.

2. File your protest

Submit your protest to the San Mateo County Assessment Appeals Board by July 2 to November 30. Include your evidence and this letter.

3. Attend your hearing

Present your case. Most hearings take 10-15 minutes. Many are resolved informally before the formal hearing date.

← California Property Tax Appeal Guide