Flat fee. We build your evidence and fill the forms — you just file, and keep 100% of your savings.
AppealKit

Last updated

Proposition 8 in San Francisco

Proposition 8 is the California rule that temporarily lowers a San Francisco assessment when market value on January 1 is below your Proposition 13 factored base-year value. The Assessor must enroll the lesser of those two numbers for that tax year. The reduction is reviewed every January 1 and does not reset your base year. San Francisco homeowners request it through a free informal review (January 2–March 31) or a formal Assessment Appeals Board filing (July 2–September 15).

That is the whole legal idea. People also call it a decline-in-value review. The two names are the same request. AppealKit is a flat-fee tool for the comparable-sales math, not a law firm, and this is not legal advice.

If you want the filing sequence rather than the rule, use how to appeal property tax in San Francisco. The local overview is the San Francisco property tax appeal hub.

What is Proposition 8, and how is it different from Proposition 13?

Proposition 13, passed in June 1978, is the ceiling. It created a base-year value (generally 1975 market value for property already owned then, or the value at a later purchase or reassessable event), limited annual inflation adjustments to no more than 2%, and capped the general tax rate at 1% plus voter-approved bonded indebtedness. That protected, factored number is what longtime owners mean when they say "my Prop 13 value."

Proposition 8, passed in November 1978, is the annual market check. San Francisco's own explanation: if current market value falls below the current assessed value (the factored base-year value) as of the January 1 lien date, the office can lower the assessment. The law requires the Assessor to enroll the lesser of market value or factored base-year value. When the market later rises back toward the base year, the enrolled value is restored up to — never above — that factored Prop 13 number (Learn about tax savings: decline-in-value).

The BOE's residential appeals guide says the same thing in hearing language: a decline-in-value appeal is only good for the year you file, the Assessor must review it again the next January 1, and a successful reduction does not become next year's starting point (Publication 30).

Is a Proposition 8 reduction permanent?

No. The Assessor's FAQ is blunt: the reduction is temporary and applies only to the tax year being appealed. Any reduced value is automatically reviewed each lien date to see whether market conditions say it should be maintained, lowered further, or increased back toward the base year (decline-in-value FAQ).

That is the feature people miss after a "win." A 2024 reduction can be gone on the 2025 roll if January 1, 2025 market value has recovered. You do not keep the low number by inertia. You also do not lose the Prop 13 ceiling: restoration stops at the factored base year, even if the market is now higher.

If you think the restored number is still above January 1 market, you ask again — informal review in Q1, formal Board filing in the July 2–September 15 window, or both.

Who actually has a Proposition 8 case in San Francisco?

People whose enrolled value is close to current market, not people whose enrolled value is a fraction of market. A longtime owner sitting on a 1990s base year is usually under-assessed on a Prop 13 basis; appealing will not help, because the Assessor already has to enroll the lower of the two figures. The people who should look:

  • Recent buyers, whose base year is last year's purchase price.
  • Anyone whose enrolled value was set in a stronger market year and has not fully come down.
  • Anyone who received a Prop 8 reduction in a prior year and then saw a large restoration on the July notice.

San Francisco is not a Texas-style unequal-appraisal jurisdiction. Showing that a neighbor on the same block is assessed lower is not the case. The case is: what would this property have sold for on January 1, and is that number below the factored base year? See assessed value vs. market value and what is an over-assessment?.

We do not publish a San Francisco win rate or a neighborhood over-assessment rate. Those figures are not on the county pages we retrieved.

How do I request a Proposition 8 reduction in San Francisco?

Two offices, two calendars, same legal theory.

Informal review, Assessor-Recorder, January 2–March 31. Free. No hearing. Eligible: single-family dwellings, condos, townhouses, live-work lofts, co-ops. Not TICs (no separate parcel number) and not third-party filings. Provide two comparable sales as close as possible to January 1 and no later than March 31. Results come in July as the Notice of Assessed Value. The Assessor also says the office tries to review declines on its own, without a request — an informal filing is how you put your comps in front of a certified appraiser (apply for a decline-in-value).

Formal appeal, Assessment Appeals Board, July 2–September 15. $120 non-refundable processing fee (waivers published on the fees page). Form BOE-305-AH. All property types, including TICs. Hearing if the parties do not stipulate. The Board can decrease, confirm, or increase the value (BOE FAQs). For FY 2026/2027 the window is July 2 through September 15, 2026 (AAB).

You may file both. Informal first does not extend September 15. The deadlines page is the clock.

What evidence supports a Proposition 8 argument?

The same evidence as any residential appeal: comparable sales timed to January 1, adjusted for differences, compared on price per square foot of living area excluding garage, porch, and patio (Publication 30). An appeals board may not consider sales more than 90 days after the valuation date. Informal review will not consider sales after March 31.

Condition still matters. A house that would have sold below the comps because of a failing roof needs the roof in the file — dated photos and a contractor's written number. A wrong square-footage figure on the property record is a fact error, and fact errors are cleaner than valuation arguments.

Neighborhood still matters. Planning's 37 named neighborhoods are how the city talks about geography; they are also why a Mission sale is a weak Prop 8 comp for Noe Valley, and why Inner Sunset is not Outer Sunset. The decline-in-value rule is citywide. The comps are not.

What will a Proposition 8 reduction change on my tax bill — and what won't it?

It changes the assessed value the Treasurer multiplies by the year's rate. For FY 2025-26 that secured rate is 1.18268325%. Direct charges and special assessments on the October bill are a different line; they generally do not fall when the roll value falls. Read how to read an SF property tax bill so you do not appeal the wrong number.

It will not grant an exemption, reverse a change-in-ownership, or cap the rate. Those are other statutes. The homeowners' exemption ($7,000 off assessed value, about $80 a year, full amount by February 15) is a parallel lever, not a Prop 8 substitute (exemption page).

Pay the December 10 and April 10 installments while any appeal is pending. A later reduction is a refund with interest, not a license to skip the bill.

How is this different from a base-year or new-construction appeal?

A Prop 8 / decline-in-value case accepts that the base year is real and argues that this January 1's market is lower. A base-year case argues that the purchase or new-construction value itself was enrolled too high, or that no reassessable event occurred. Those are different boxes on BOE-305-AH, different valuation dates (event date vs January 1), and different filing windows (including a 60-day supplemental clock). Marking the wrong reason can get an application dismissed (Publication 30). If you just bought, read the notice: you may have both a supplemental 60-day issue and a later regular-roll Prop 8 issue. They are not the same filing.

When you want to know whether January 1 comps sit below your enrolled value, the free check runs that comparison. If they do not, a Prop 8 filing is not the move — and we will say so.

What happens in year two after a Proposition 8 reduction?

Year two is why people feel baited. The Assessor reviews the property again on the next January 1 and enrolls the lesser of current market or the factored base year. If the market has bounced, the enrolled value climbs — not because you "lost" a permanent cut, but because the cut was never permanent (decline-in-value FAQ). You can ask again. You file a new informal review in Q1 and/or a new formal application in the next July 2–September 15 window. Publication 30 is explicit: a decline-in-value appeal does not carry forward; you file each year you disagree (Publication 30).

The 2% inflation factor still applies to the base year, not to a Prop 8 number you wish would stick. When market value exceeds the factored base year, the enrolled value returns to that factored number and stops. It does not jump to full current market. That is the Prop 13 ceiling doing its job. The people surprised by a restoration are often last-cycle Prop 8 recipients who treated the low number as a new base. It was not.

If new construction or a change in ownership happened in the meantime, you may also have a supplemental 60-day clock that is not a Prop 8 filing at all. Mark the right box on BOE-305-AH. The deadlines page is the calendar; this section is the reason the calendar repeats.

A related honest limit: the Board cannot reduce an assessment because taxes went up from prior years, cannot grant the homeowners' exemption, and cannot lower the rate (Publication 30). Prop 8 is a market-value statute. Bring comparable sales, not a printout of last year's bill.

One more annual mechanic: the Assessor can enroll a decline without you asking. That does not close the Board's door. If the July notice still sits above what January 1 comps support, the formal window is how you get an independent panel. If the notice already matches the comps, stop. A hearing in search of a still-lower number, with thin evidence, is how the Board's power to increase becomes relevant (BOE FAQs).

FAQ

What is Proposition 8 in San Francisco?

A temporary decline-in-value reduction. When January 1 market value is below your Proposition 13 factored base-year value, the Assessor must enroll the lower number for that tax year (sf.gov decline-in-value).

Is a Prop 8 reduction permanent?

No. It is reviewed every January 1 and can be restored up to the factored base year if the market recovers. It does not reset the Prop 13 base (sf.gov FAQ; Publication 30).

Can the Assessor restore my value next year without a new hearing?

Yes. Once a decline is enrolled, the office reviews it annually. Restoration toward the base year is the designed behavior, not a penalty (sf.gov).

Do I need to appeal if the Assessor already reviews declines?

The office says it tries to. An informal review is how you put your own January 1 comps in the file. A formal appeal is how you get an independent Board to decide if you disagree with July's notice (sf.gov apply-decline-value).

Does Proposition 8 help if my neighbor is assessed lower?

Not by itself. California's residential case is market value as of January 1, not an equal-and-uniform comparison to a neighbor's roll number. Use comparable sales, not the neighbor's tax bill.

Are TIC owners eligible?

Not for informal review. TIC owners file a formal Application for Changed Assessment with the Assessment Appeals Board between July 2 and September 15 (sf.gov FAQ).

What is the deadline to ask for a Prop 8 reduction?

Informal: January 2–March 31 (closed for 2026). Formal: July 2–September 15 (September 15, 2026 for the current regular roll). Informal does not extend formal (sf.gov).

Will a Prop 8 reduction lower my special assessments?

Usually not. Those are direct charges on the Treasurer's bill, not the assessed-value line the Board equalizes (Treasurer; how-to-read-the-bill guide).

Related

Sources

See if you're over-assessed — free

No account, no email needed to see your result.

Check my property — free

This is general information, not legal or tax advice. AppealKit is a self-service tool, not your representative.