How to Appeal Your Property Tax in San Francisco
If your San Francisco home is assessed for more than it's worth, you have two ways to fix it: a free informal review with the Assessor-Recorder (January 2 – March 31) and a formal appeal to the Assessment Appeals Board (July 2 – September 15). The two windows never overlap — and most homeowners can handle either one without a lawyer.
What are the two ways to appeal my property tax?
San Francisco offers two paths: a free informal review through the Office of the Assessor-Recorder, City and County of San Francisco, or a formal appeal through the San Francisco Assessment Appeals Board. Unlike most California counties, the two run on calendars that never touch: informal January 2 – March 31, formal July 2 – September 15. Whichever window is open decides your move.
What is an informal review?
Through the Office of the Assessor-Recorder, City and County of San Francisco
The informal review (an “Informal Assessment Review Request”) is a free ask to the Assessor — no hearing, no fee, no lawyer. Between January 2 and March 31 you submit your opinion of your home's January 1 market value with two comparable sales, preferably through the Assessor's online community portal (or by mail, fax, or email). An appraiser reviews the evidence, and the result shows up in your Notice of Assessed Value in July. Your value cannot go up as a result of this request.
- Free to file — no fee
- Filed online through the Assessor's community portal — or mail, fax, or email the form
- Two comparable sales, closed no later than March 31 — later sales won't be considered
- Residential properties only — TIC owners (no separate parcel number) go straight to the formal appeal
The window closes March 31 — and doesn't come back
Miss March 31 and the informal review is gone for the year. There's no overlap with the formal window and no extension — your next move is the formal appeal in July.
What is a formal property tax appeal?
Through the San Francisco Assessment Appeals Board
The formal appeal is filed with the Assessment Appeals Board using San Francisco's own version of the BOE-305-AH (“Assessment Appeal Application”), with a $120 nonrefundable fee. San Francisco is one of the few counties with real online filing — the portal at aab.sfgov.org takes your application and credit-card payment for regular assessment appeals. It leads to a hearing at City Hall where either a single Hearing Officer (residential, 4 units or fewer) or a three-member Board weighs your evidence against the Assessor's and can lower, confirm, or in rare cases raise the value.
- Filing window: July 2 – September 15 each year (online filings by 11:59 PM on the deadline)
- $120 nonrefundable filing fee — waived for court-fee-waiver qualifiers, assessments of $7,500 or less, or a value gap of $7,500 or less
- File online at aab.sfgov.org — or on paper with an original blue-ink signature (SF's own form version only)
- Hearings in person at City Hall, Room 405 — Hearing Officer option for residential of 4 units or fewer
Expect a wait — San Francisco has a record backlog
The Board processed 9,281 applications in fiscal year 2024–25 (up from 1,417 five years earlier), so hearings can take many months to over a year. The law requires a decision within 2 years of a timely filing — and if your value is reduced, the overpaid tax is refunded with interest.
The sequence that works in San Francisco: file the free informal review by March 31, read the Notice of Assessed Value in July, and if the value isn't where the evidence says it should be, file the formal appeal by September 15. You can't file both at once — the windows never overlap — so the calendar, not a dual-filing strategy, does the protecting here.
14 days left to file a formal appeal in San Francisco County
Applications must reach the San Francisco Assessment Appeals Board by September 15. The filing fee is $120. Miss it and the next opportunity is next year's filing window.
Not sure you have a case? Check your property free — about 60 seconds, and if you're not overassessed we'll tell you so.
San Francisco County filing dates and cost, at a glance
- Informal review
- January 2 – March 31Free
- Formal appeal
- July 2 – September 15
- Formal filing fee
- $120 per parcel
Can't afford the fee? The $120 fee is waived if you qualify for a California court fee waiver (Government Code § 68632 — the same low-income standard courts use), if your property is assessed at $7,500 or less, or if the gap between the assessed value and your opinion of value is $7,500 or less. Ask the Assessment Appeals Board clerk when you file.
Want every date for San Francisco County in one place — bill due dates, supplemental assessment clocks, and what to do if you miss a window? See the San Francisco County property tax deadlines page.
What evidence do I need for a property tax appeal?
Comparable sales are the heart of a San Francisco appeal: recent closed sales of similar nearby homes that show the market was below your assessed value on January 1. The Board may not consider sales that closed more than 90 days after January 1, and the informal review is tighter still — sales after March 31 won't be considered. Listings and Zestimate-style estimates are not evidence. For condos — the softest segment of the SF market and the core appeal opportunity — same-building or very similar building sales are strongest, adjusted for parking, floor, view, outdoor space, and HOA dues.
“Similar” means comparable in:
- Square footage and lot size
- Bedrooms and bathrooms
- Condition and age
- Proximity to your home (within about a mile)
On your own home, the Assessor carries the burden of proof
For an owner-occupied single-family home with the homeowners' exemption, the Assessor bears the burden of proof at the formal hearing and presents first — not you. Good comparable sales evidence tilts the field further in your favor. And don't attach evidence to the application — the form says not to; you present it at the hearing.
Free data sources: The SF Property Information Map shows your parcel number (Block/Lot), taxable values, and property characteristics, and the AAB forms page offers a free Residential Comparison Work Sheet for organizing comps.
This is what Overassessed does. We find comparable sales from county records, calculate professional-grade adjustments for differences in size, features, and condition, and package the evidence you need — ready to submit.
The Overassessed Filing Guide includes comparable sales data, dollar adjustments, and a ready-to-submit value argument — everything listed above.
See what's includedHow do I file a property tax appeal step by step?
The process runs on one calendar: informal review by March 31, Notice of Assessed Value in July, formal filing by September 15. Here's the whole thing, start to finish.
Check your assessed value
Look up your parcel on the SF Property Information Map or your Notice of Assessed Value (mailed by August 1) and compare the assessed value to what your home was actually worth on January 1. If the market value is lower, you likely qualify.
Overassessed does this for you — enter your address and we'll pull your assessment and run the comparison.
Gather comparable sales
Collect 3–5 recent sales of similar nearby homes. For the informal review, sales must have closed no later than March 31; for the formal hearing, no more than 90 days after January 1.
The Overassessed Filing Guide includes selected comps with professional-grade adjustments, ready to copy in.
File the free informal review by March 31
Between January 2 and March 31, submit the Informal Assessment Review Request through the Assessor-Recorder's community portal (preferred) with your opinion of value and two comparable sales — or mail, fax, or email the form to the Assessor's office at City Hall Room 190. Residential only; the owner must file personally.
File the formal appeal by September 15
If the July notice doesn't reflect a reduction — or the informal window already closed — file San Francisco's own Assessment Appeal Application between July 2 and September 15: online at aab.sfgov.org with the $120 fee by credit card (received by 11:59 PM on September 15), or on paper with an original blue-ink signature and a check to CCSF, delivered to City Hall Room 405. State your opinion of value — don't leave it blank — and don't attach evidence.
Prepare for your hearing
Hearings are in person at City Hall Room 405. For residential properties of 4 units or fewer, electing a single Hearing Officer is less formal and skips the hearing fee — bring 3 sets of your documents (6 sets for a full Board panel). Keep paying your tax bills; a successful appeal is refunded with interest.
Our Filing Guide gives you copy-ready values for both the informal form and the formal application, plus a deadline tracker.
Check if you qualifyImportant things to know
The two windows never overlap
The free informal review closes March 31 and the formal appeal closes September 15 — with a gap in between. If it's past March 31, your only path for this year is the $120 formal appeal by September 15. Miss that too and there's no do-over until next January.
San Francisco is a September 15 county
Some California counties allow formal filings through November 30 — San Francisco does not. Because the Assessor mails value notices to all owners by August 1, the formal window is July 2 – September 15. Don't borrow another county's deadline.
The formal appeal costs $120 — the informal review is free
The $120 fee (effective August 2025) is nonrefundable win or lose — but it's waived if you qualify for a court fee waiver, if your property is assessed at $7,500 or less, or if the gap between the assessed value and your opinion of value is $7,500 or less. Against typical San Francisco values, a successful appeal usually saves many times the fee every year.
Paperwork traps that sink otherwise-good appeals
San Francisco accepts only its own version of the appeal form — not another county's or the state BOE's blank. Paper filings need an original blue-ink signature. File one application per parcel, per tax year — a prior year's reduction doesn't carry forward. Don't leave your opinion of value blank, don't attach evidence to the application, and don't miss your hearing — nonappearance means denial.
The Board can raise a value at a formal hearing — the Assessor can't on informal review
The informal review is risk-free: reduce or confirm, never increase. At a formal hearing the Board can raise, lower, or confirm the value based on the evidence — increases are rare in decline-in-value cases, and strong comparable sales are your protection.
The backlog is real — and the clock works in your favor
With 9,281 applications filed in fiscal year 2024–25, hearings can take many months to over a year. But the Board must decide within 2 years of a timely filing, refunds come with interest, and many cases settle earlier by written stipulation with the Assessor's office. Keep paying your installments (December 10 and April 10) while you wait.
TIC owners: skip the informal review
Tenancy-in-common interests don't have separate parcel numbers, so the informal review isn't available — a TIC appeal goes straight to the formal Assessment Appeals Board during the July 2 – September 15 window.
Frequently asked questions about San Francisco property tax appeals
What is the deadline to appeal property taxes in San Francisco?
There are two windows, and they never overlap. The free informal review with the Office of the Assessor-Recorder, City and County of San Francisco runs January 2 – March 31. The formal appeal with the San Francisco Assessment Appeals Board runs July 2 – September 15 — file online at aab.sfgov.org by 11:59 PM on September 15, or get a postmark by that date. If March 31 has passed, the September 15 formal appeal is your only option for the year.
How much does it cost to appeal my property tax in San Francisco?
The informal review is completely free. The formal appeal costs $120 per application (nonrefundable), payable by credit card online or by check to CCSF by mail. The fee is waived if you qualify for a California court fee waiver, if your property is assessed at $7,500 or less, or if the difference between the assessed value and your opinion of value is $7,500 or less. Details are on the county's Assessment Appeals Board fees page.
Informal review vs. formal appeal in San Francisco — which should I do?
If it's before March 31: start with the free informal review — no fee, no hearing, and the Assessor can only lower or confirm your value. Results arrive in July with the Notice of Assessed Value, before the formal window even opens, so you can still file the formal appeal by September 15 if the result disappoints. If it's after March 31: the formal appeal is the only path for this year. Note the informal review is residential-only and TIC owners can't use it.
Can my assessment go UP if I appeal in San Francisco?
Not in an informal review — the Assessor can only reduce or confirm your value. At a formal Assessment Appeals Board hearing, the Board does have the authority to raise, lower, or confirm the value based on the evidence. Increases are rare in decline-in-value cases, and strong comparable sales evidence is your protection.
Do I still pay my tax bill while my San Francisco appeal is pending?
Yes — pay every installment on time (December 10 and April 10), or a 10% penalty applies regardless of how the appeal turns out. San Francisco's appeal backlog means decisions can take a long time, but if your value is reduced, the Treasurer & Tax Collector refunds the difference with interest.
What evidence do I need — can I use Zillow?
Closed comparable sales near the January 1 lien date are the evidence that works: 3–5 sales of similar nearby homes, adjusted for differences. Listings and Zestimate-style estimates are not evidence. The Board may not consider sales that closed more than 90 days after January 1, and the informal review uses an even tighter March 31 cutoff. For condos, same-building or very similar building sales are strongest.
Does filing the free informal review protect my appeal deadline in San Francisco?
No. The informal review doesn't pause or extend anything, and because San Francisco's windows never overlap, you can't file both at once. The sequence that works: informal review by March 31, check the July Notice of Assessed Value, and if the value isn't where the evidence says it should be, file the formal appeal by September 15.
How long does a San Francisco property tax appeal take?
Longer than usual right now. The Assessment Appeals Board processed 9,281 applications in fiscal year 2024–25 — up from 1,417 five years earlier — so residential hearings can take many months to over a year. The law requires a decision within 2 years of a timely filing. Many cases settle earlier by written stipulation with the Assessor's office, without a hearing.
Official county resources: the decline-in-value review page, the Assessment Appeals Board FAQs, the online filing portal, the SF Property Information Map, and every San Francisco deadline in one place.
Ready to see if you qualify?
Enter your address and we'll compare your assessed value to comparable sales. It takes about 60 seconds.
Overassessed provides estimates based on publicly available data and AI-generated analysis. This is not a formal appraisal, legal advice, or tax advice. Results are not guaranteed, and appeal outcomes depend on county review. Users file their own appeals. AI-generated estimates may differ from actual market values.