County filing guide
How to appeal your property tax in San Diego County
Regular decline-in-value appeals. Supplemental and escape assessments have different deadlines.
Filing options
Filing instructions
Informal review
The informal review window for 2026-27 has closed (it ran through April 30, 2026). Check the county's page for next cycle's review window. These instructions remain available as a reference.
Open the Assessor’s realty assessment page and select Prop 8.
Assessor’s Prop 8 page Open the Assessor Forms page and find Real Property Assessment → Review of Assessment (Prop 8). The county makes the form available during December 1, 2025–April 30, 2026; the download is currently unavailable. During that window, download it there or obtain it from an ARCC branch office.
San Diego informal review — step 2 Complete the form with your opinion of value and supporting comparable sales.
Return the completed form to the Assessor following its submission instructions and keep a copy. For help obtaining or returning the form, call 858-505-6262.
Formal appeal online
Open the San Diego assessment appeals portal. Choose Register for a new account, or Go To Login if you already have one.
Portal with Register and Go To Login marked Enter your first name and email. Last name and phone are optional on this screen. Read the terms, select the agreement checkbox, and choose Continue.
Registration details and Continue marked Create and confirm your password, then use Verify your account in the verification email. Sign in.
From the dashboard, choose Create appeal. Select the assessment type and roll year. For an annual 2026 value appeal, select the regular assessment and 2026.
Choose Owner if filing for yourself. Complete your contact and mailing details and choose how to receive notices.
Identify the property by parcel or tax bill number and address. Enter the Assessor’s enrolled value and your opinion of value.
Select the appeal reason, answer the written-findings question, and upload documents requested by the portal. Follow its instructions about evidence to provide later.
Review the application, complete the declaration and electronic signature, and choose Submit.
Keep a copy and check the dashboard for updates. The Clerk reviews the submission; an appeal number is assigned after acceptance.
After you file
Informal review
Keep your request confirmation and any correspondence from the Assessor. Check the formal appeal deadline above when considering a separate appeal.
Formal appeal
Keep a copy of your application and filing confirmation. Watch for notices from the Clerk of the Board and follow the county’s instructions for any hearing.
Open my appeal plans →Contacts & sources
Clerk of the Board
Runs the formal appeal
619-531-5777 · appeals page ↗
1600 Pacific Highway, Room 402, San Diego, CA 92101-2471
This guide covers the regular decline-in-value appeal; supplemental or escape assessment notices follow different deadlines. Every date and fee here was checked against official sources, listed below with the date checked. If the county's page ever differs from this guide, follow the county's page.
Sources
Informal sources
- Assessor’s realty assessment page — Prop 8: describes the free review and the December 1–April 30 request window; the form is available during that period.
- ARCC office locations.
- Assessor Forms page: lists Review of Assessment (Prop 8) under Real Property Assessment, but without a download link as of September 29, 2026. The indexed county PDF at real-property-assessment/valrev.pdf returned HTTP 404 when checked.
- Scope: public county pages checked September 29, 2026. Original Prop 8 screenshot retained; the Assessor Forms screenshot was captured and annotated September 29, 2026. A currently downloadable form and a completed informal submission were not verified.
Informal review
- https://www.sdarcc.gov/content/arcc/home/divisions/assessor/realty-assessment.html · “The Review of Assessment (Proposition 8) form is available from December 1st through April 30th online and at all ARCC branch offices. Applications can be submitted from December 1st through April 30th.” (checked July 11, 2026)
- https://www.sdarcc.gov/content/arcc/home/divisions/assessor/realty-assessment.html · “While property owners are certainly at liberty to use these private companies, they can apply for this reduction themselves at absolutely no cost.” (checked July 11, 2026)
Formal sources
- County instructions for filing and managing an appeal: source for the steps after registration.
- Assessment Appeals Board: regular filing window is July 2–November 30.
- County announcement of online filing: September 3, 2026 launch.
- Scope: portal entry and initial registration screen inspected September 29, 2026; screenshots annotated from those screens. Password verification and the signed-in application steps follow the county’s published instructions. No account was created and no appeal was submitted.
Formal appeal window
- https://www.boe.ca.gov/proptaxes/pdf/lta26023.pdf · “The regular appeals filing period in each county will begin on July 2, 2026, and will end on September 15, 2026, for those counties where the Assessor mails assessment notices to all taxpayers with property on the secured roll by August 1, 2026. For counties where assessment notices are not mailed by August 1, 2026, the filing period is extended to November 30, 2026.” (checked July 10, 2026)
Filing fee
- https://www.sandiegocounty.gov/content/sdc/cob/aab/agenda.html · “Property owners in the County of San Diego may file an Assessment Appeal Application with the Clerk of the Board of Supervisors. There is no fee for this service.” (checked July 26, 2026)
Filing address
- https://www.sandiegocounty.gov/content/sdc/cob/aab/filingguide.html · “Applications may be filed in person at 1600 Pacific Highway, Room 402, San Diego, CA 92101-2471 or by mail.” (checked July 11, 2026)
Filing channels
- https://www.sandiegocounty.gov/content/sdc/cob/Assessment-Appeals/file-and-manage/ · “You can file: Online By mail In person” (checked September 29, 2026)
Common questions about appealing in San Diego County
When is the deadline to appeal in San Diego County?
The deadline to file a formal appeal in San Diego County for the 2026-27 tax year is November 30, 2026. Filing opened July 2, 2026.
The Assessor's informal review window ran from December 1, 2025 to April 30, 2026.
What does it cost to file an appeal in San Diego County?
San Diego County charges no fee to file a formal appeal.
There is no fee for the Assessor's informal review.
Informal review or formal appeal: which one first?
San Diego County offers both: an informal review with the Assessor, and a formal appeal filed with the Clerk of the Board (due November 30, 2026).
The state's own guidance says to talk to the Assessor's office first: if their staff finds an error, they can lower the roll directly and you may never need to file. Missing an informal review costs you nothing; missing the formal deadline costs you the year.
Which form do I file, and where?
The formal appeal uses San Diego County's own application form, Assessment Appeal Application ↗.
San Diego County accepts the formal appeal online, by mail, or in person. File online through the county's appeals portal ↗.
Mail it to the Clerk of the Board at 1600 Pacific Highway, Room 402, San Diego, CA 92101-2471.
Check the Clerk of the Board's appeals page ↗ or call 619-531-5777 before you file.
How long does an appeal take?
You get written notice at least 45 days ahead, hearings are open to the public (you can watch one first), and boards are expected to decide within two years of filing. You can still settle at any point before your date.
Do homeowners actually get their assessments lowered?
San Diego County reduced assessments on over 18,000 homes, saving homeowners $15 million in 2023-24.