Cut the property tax rate by a third. Assess everyone the same way.
One Rate California is a revenue-neutral reform: replace Prop 13's frozen, purchase-price assessments with consistent market-value assessments statewide, and cut the general property tax rate from 1% to roughly two-thirds of 1% — so the reform doesn't raise a dollar more revenue than today. It just spreads the same total bill more evenly.
Our own data: San Francisco, 2026
Every one of San Francisco's roughly 154,000 single-family homes and condos, plus ~35,000 multi-family buildings, built from the city's own current public assessment records rather than a third party's — so it's specific to San Francisco, but newer than the map above. Small circles are individual homes/condos; larger white-ringed circles are whole apartment/rental buildings, colored by estimated property tax subsidy either way.
Drag to pan, scroll or double-click/pinch to zoom, click any home for its numbers. Zoom in (or pick a neighborhood above) to see its boundary and average subsidy. Map data © OpenStreetMap contributors.
Methodology
Assessed values come directly from the San Francisco Assessor-Recorder's official public dataset (DataSF: Assessor Historical Secured Property Tax Rolls). Since there's no open dataset of actual sale prices, current market value is estimated: for each home, we find nearby "comps" whose assessed value recently reset to a real market level, then apply their median price-per-square-foot to the home in question. A reset is confirmed by checking multiple years of each parcel's own assessment history — Prop 13 caps ordinary inflation adjustments at about 2% a year, so a jump larger than that, together with a recorded sale nearby, means an actual reassessment happened. This catches non-arms-length transfers (family and trust transfers, batch administrative recordings) that have a sale date on file but never reset to market value, and would otherwise distort the comps.
Checked against homes that themselves sold in 2024–2025 (so their true value is essentially known), this estimate lands within 20% of the real value about 64% of the time, with a median error of about 14%. It's least reliable at the very top of the market, where a simple nearby-comps approach undershoots distinctive, high-end properties. Treat every number here as a rough estimate, not an appraisal — county bond rates are held at San Francisco's ~0.18% for simplicity, and the same general tax rates used in the calculator above (1.00% today, ~0.65% proposed) are applied throughout.
Multi-family buildings (larger, white-ringed circles) use a simpler, rougher method, since actual building sales are much less frequent: rather than nearest individual comps, every confirmed sale in a neighborhood is averaged into one $/sqft figure, applied to every building in that neighborhood. Neighborhoods with too few confirmed sales fall back to a $/sqft average pooled from their 5 nearest neighborhoods instead. This values the whole building at once, not individual units — the map's per-unit figures simply divide that building-level number evenly across units, which won't match any specific unit's real value. It says nothing about any tenant's actual rent, only about the building owner's assessed-vs-market tax gap.
The unfairness, mapped
Every dot is a real Bay Area home, colored by its property tax subsidy — the gap between what it actually pays and what it would pay if assessed at today's market value. Map and data: The Tax Fairness Project.
Map © The Tax Fairness Project — open full interactive map ↗ (data reflects 2019–2020 county records and valuation estimates).
Same street. Same value. Very different bills.
Bought in 1995
- Assessed value today
- $210,000
- Current market value
- $950,000
- Current tax bill
- $2,478/yr
Bought in 2023
- Assessed value today
- $945,000
- Current market value
- $950,000
- Current tax bill
- $11,151/yr
Two homes on the same block, worth almost exactly the same amount today — but one bill is more than four times the other, purely because of when each was purchased. That gap keeps widening every year prices rise.
Illustrative example; not actual properties.
The proposal, in three parts
All three pieces move together — none of them makes sense as a standalone change.
Assess consistently, at market value
Replace Prop 13's acquisition-value system — where a property's taxable value is frozen at its purchase price and can rise at most 2% a year — with regular assessment at current market value, applied the same way to every property.
Cut the general rate by about a third
Lower the general property tax rate from 1.00% to roughly two-thirds of 1% (about 0.65%), so that statewide revenue stays approximately flat once the assessment base widens. This is a rate cut, not a new tax.
Preserve existing voter-approved bonds
Local bond and assessment rates that voters already approved to repay specific debts stay in place, unchanged, on top of the general rate — only as much as needed to service that existing debt.
How the increase is phased in
A lower rate and consistent assessment don't mean every affected bill changes overnight. Nobody should have to move out of a home they can otherwise afford just to cover the change.
The gap between assessed and market value doesn't just disappear in the meantime, though. Each year's shortfall accrues, and becomes payable when the home is next sold or transferred — including by inheritance. In effect, a longtime owner gets a capped, predictable annual increase for as long as they keep the home; the rest is settled at the point where the property's value question gets resolved anyway.
Honest caveat: a 4%-a-year cap closes a small gap quickly, but a very large one slowly — take the 1995-purchase example above, and closing that gap through the annual cap alone would take decades. For homes with a gap that big, the deferred amount due at sale is doing most of the real work, not the annual cap. The calculator above shows the fully phased-in bill, not this year's capped payment.
Calculator: what would this mean for your bill?
Enter numbers from your own property tax bill, or start with the pre-filled example. Every figure below is adjustable — nothing here is a hidden assumption.
Today, under Prop 13
$0/yr
Under this reform
$0/yr
Illustrative estimates based on the numbers you enter — not tax advice or an official projection.
Honest FAQ
Straight answers, including the ones that don't help the pitch.
Will my taxes go up?
It depends on how your current assessed value compares to today's market value — use the calculator above with your own numbers to see where you land. If you bought recently, or your assessed value is already close to market value, your bill would likely fall, since the general rate itself drops by about a third. If you've owned your home a long time in an area where prices have risen a lot, your assessed value is probably far below market value, and your bill would eventually rise to reflect that — but not all at once. See how the increase phases in below.
What about seniors on fixed incomes?
This is the single biggest legitimate concern with an idea like this, and it deserves a straight answer, not a dodge. That's what the transition mechanism above is for: your annual bill can only rise 4% a year no matter how far below market your assessed value is, for as long as you keep the home. Nobody has to move, or find a lump sum, to cover the difference — the difference is deferred, not forgiven, and comes due at the next sale or transfer.
Is this a tax increase?
Statewide, it's designed to be revenue-neutral: the rate is cut by about a third specifically to offset the fact that everyone would be assessed at market value instead of a frozen purchase price. It is not a hidden way to fund new spending, and this page does not promise new money for schools, services, or infrastructure — that would be a different, revenue-positive proposal. But "revenue-neutral in aggregate" does not mean "no individual bill changes." Some go up, some go down — see "Will my taxes go up?" above.
What happens to Prop 13's other protections?
Prop 13 bundles several distinct protections: it caps the general property tax rate at 1%, it freezes assessments at purchase price with at most a 2%-a-year increase, and it requires a two-thirds vote for certain new state taxes. This proposal touches only the first two, and only for the general rate and the acquisition-value assessment rule — it does not change the supermajority vote requirement for new taxes, and it does not, on its own, change transfer, exemption, or inheritance rules beyond what's needed to assess property consistently.
Who pays more under this?
Owners whose current assessed value is well below today's market value — typically people who have owned the same property for a long time in places where prices climbed a lot in the meantime. Their share of the tax base rises to match what their property is actually worth today, even as the rate itself falls.
Who pays less?
Owners whose assessed value is already close to market value — typically people who bought more recently. They see the direct benefit of the rate cut without a matching jump in their taxable value, so their bill falls by roughly the same one-third the rate falls.
Get involved
Californians for Fair Property Taxes is a new effort, formed in 2026 — we're still building out the campaign. Sign-ups aren't active yet, but this is where updates will go out as the details, and the rest of our plan, come together.
Not active yet — check back soon.