Application and Instructions



Regular Assessments Filing dates are July 2 through November 30, 2023 for all real and personal property assessments.
Supplemental Assessments Filing dates are within 60 days of the mailing date printed on the Supplemental Notice.
Escape Assessments Filing dates are within 60 days of the mailing date printed on the Escape Notice.
Calamity Reassessments Filing dates are within six months after the mailing date of the proposed reassessment notice.

Please refer to the instruction sheet for specific information. For additional help in filling out the application, please refer to Publication 30 - Residential Property Assessment Appeals. You may also find the videos prepared by the State Board of Equalization helpful. If you are having problems downloading the application form, you can contact the Assessment Appeals Board Clerk (650 363-4573 or to have the application form sent to you.

Please note that ALL questions on the application must be answered. Failure to do so may result in the return of your application for incomplete filing and will delay the processing of your application. These are common errors that occur in the following sections:

  • Section 2, Agent : Applicants are not required to have an agent; however, if you have an agent, you must either authorize such representation by providing a "Signature of Applicant/Officer/Authorized Employee" in Section 2 or attach a separate Agent Authorization. Please note that we will be sending the hearing notices to the agent.

  • Section 4, Value: The "Value On Roll" (Box A) is the assessed value that you want to appeal. This information can be found on your tax bill. If you are unsure, you may call the Assessor's office for more information (650 599-1227). The "Applicant's Opinion of Value" (Box B) is your opinion of value. Both columns must be completed.
  • Section 5, Type of Assessment Being Appealed and Their Filing Periods: Only one type of assessment may be checked and only one tax year may be specified. A separate application must be filed for each year.
  • Section 6, The Facts: Check any or all that apply; this is the basis of your appeal. If you check Box I ("Other"), be sure to attach a more detailed written explanation.
  • Section 6, B and C: Check one of these boxes if you are appealing the property's base year value following a change in ownership or new construction. A prior base year value may also be challenged on a regular assessment appeal if you check one of the boxes in Section 6, B or C. If your appeal is successful, such relief would only be prospective.
  • Section 7, Written Findings: Written Findings of Fact are necessary if you plan to appeal an adverse decision in Superior Court. It is a legal brief compiled by County Counsel explaining the Board’s decision and must be requested before the hearing. You will be asked to confirm this request on the day of the hearing before your hearing begins. All fees must be paid in full at the conclusion of the hearing. Fees are set at $500 per hour of hearing time or fraction thereof. For example, a hearing that lasts 45 minutes will cost $500.00. A hearing that lasts 1 hour and 10 minutes will cost $1000. You must pay this fee to the Assessment Appeals Board Clerk with either check or cash.
  • Section 8, Claim for Refund: If you want to make this application to also serve as a claim for refund, check "yes." This will enable the county to automatically process a refund to you if the Assessment Appeals Board reduces the value of your property. However, this option may not be in your best interest if you intend to file action in Superior Court. Please refer to Publication 30 for more details.

  • Sign your application form

You can only appeal one year and one parcel number per application. If you are uncertain of your parcel number, please refer to your tax bill or the San Mateo County Treasurer-Tax Collector's Website to lookup your parcel number.

Be sure that your application is submitted on time; there are no deadline extensions or exceptions regardless of your circumstances.

Your application should include the following:

  • The original application with wet signature
  • $30.00 filing fee for each application; checks must be made payable to San Mateo County AAB

All applications must be sent to or hand deliver to: 

San Mateo County Assessment Appeals Board
400 County Center, BOS 104
Redwood City, CA 94063


Your property taxes

Do I still need to pay my property taxes?

Yes. You must still pay your property taxes on time. If you are granted a reduction, you will receive a refund and interest.

After the application has been submitted

What happens after you submit your application?

The Assessment Appeals Board (AAB) clerk will review your application. If the application is properly completed, your application will be processed and a hearing date will be scheduled. A hearing will be set within approximately 2 to 3 months (NOTE: due to the volume of applications, this may be longer and time must be allowed to properly notify you of the hearing date). If the application was deficient or incorrectly filled out, you will generally have 30 days to resubmit the application or your application will be denied for an invalid application.

When your application is accepted, a copy of your application is forwarded to the Assessor's office for review. The Assessor's office may make a determination of the value of the property and contact you. If you and the Assessor's office can reach an agreement on the value of the property, you will be asked to sign a stipulation. A stipulation is simply an agreement made between you and the Assessor as to the value of the property and does not require a hearing. The stipulation must be approved by the AAB; if the AAB does not approve the stipulation, you will be required to appear before the AAB and the AAB Clerk will notify you at least 45 days in advance of the hearing date. If no agreement can be reached, you must attend the scheduled pre-hearing conference before the Assessment Appeals Board. The AAB clerk will notify you, in writing, of the time, date, and location of your hearing at least 45 days in advance. Generally, hearings are held every other Thursdays of the month.

Amending the application

Can I amend my application?

You may file an amended application no later than 5:00 p.m. on the final filing date for the type of assessment being appealed (for regular appeals, the last date for amended application is November 30, 2023 and for supplemental/escape assessment, the last date is the 60th day from the notice date). After that time, corrections of a clerical nature can be made by contacting the AAB Clerk. If the amendment is substantive, the changes may be made at the discretion of the AAB at the hearing.