LA Condo Property Taxes: Prop 13, Supplemental Bills and Measure ULA

Property tax is the line item LA condo buyers most often estimate wrong. California does not tax your unit on what it is worth today; under Proposition 13 it taxes what you paid for it, then adds a one-time supplemental bill after closing and, at the high end, a City of Los Angeles transfer tax called Measure ULA. Here is how the three fit together, and where to verify what applies to your deal.

How Prop 13 ties your tax to what you paid

California runs an acquisition-value property tax system under Proposition 13, passed in 1978. Rather than reassessing your condo to current market value every year, the county sets its assessed value when you acquire it; in an ordinary arm's-length sale, that is essentially your purchase price. The base tax rate is 1 percent of that assessed value. On top of the base sit voter-approved add-ons, mostly to repay local general-obligation bonds for schools and infrastructure, which is why a real LA tax bill runs a little above 1 percent. Once set, your value can rise only a capped amount each year for inflation, no more than 2 percent annually, however fast the market climbs. The add-ons vary by parcel, so confirm the exact combined rate with the county or a tax professional.

Why the identical unit down the hall pays less

Because the basis is set at acquisition, two identical condos in one building can carry very different tax bills. A neighbor who bought a decade ago holds a low assessed value that has only crept up by the inflation cap; when you buy today, your basis resets to today's price. That reset is the thing buyers most misunderstand about LA property tax: you do not inherit the seller's Prop 13 basis, and a listing's quoted taxes usually reflect that seller's old, lower assessment, not what you will pay. Estimate your bill from your purchase price and the combined rate, not from the current owner's number.

The supplemental bill that lands after you close

When ownership changes, the assessor reassesses the property and issues a supplemental assessment: the difference between the seller's old assessed value and your new one. This produces a supplemental tax bill, separate from the regular annual bill and prorated for the part of the fiscal year (July 1 through June 30) remaining after you close. Depending on when you buy, you may receive one supplemental bill or two. Here is the trap: these bills are mailed directly to you and are generally not paid from the impound or escrow account your lender set up for the regular installments. Buyers who assume the mortgage covers everything get a real bill weeks or months after moving in. Set money aside for it.

Measure ULA and the City of LA transfer tax

Separate from the annual tax is a one-time tax on the sale itself. Measure ULA, approved by City of Los Angeles voters in 2022 and effective April 2023, taxes high-value real-estate transfers within the city to fund housing and homelessness programs. As enacted it applied 4 percent to transfers at or above $5 million and 5.5 percent at or above $10 million; those thresholds are adjusted for inflation each year, so confirm the current figures with a tax professional or the city. Two features matter most. First, it is a cliff, not a marginal bracket: the rate applies to the entire price, so a sale one dollar over a threshold owes the full percentage on the whole amount. Second, it is customarily paid by the seller and sits on top of the older city and county documentary transfer taxes. Despite its mansion-tax nickname, it covers all property types, not only homes.

Which LA condos actually cross the line

For most condo buyers, ULA is a non-event. Our neighborhood research puts the median condo price around $645,000 in Downtown LA and 640,000 in Koreatown, per-our-research estimates, with current figures at /market-stats; both sit far below the high-value thresholds. Where ULA comes into view is the top of the market: our research pegs Century City's median near $1.65 million, with towers reaching well beyond, so a large penthouse can approach ULA territory. Geography matters too, because the tax applies only inside City of Los Angeles limits. Downtown, Westwood, Century City and Playa Vista are in the city; West Hollywood, Beverly Hills and Santa Monica are their own cities, and Marina del Rey is unincorporated county, none of them subject to ULA, though several of those jurisdictions levy their own transfer taxes. Know which city your building sits in.

Downsizers, inheritance and moving your basis

Prop 13 shapes later moves too. Under Proposition 19, homeowners who are 55 or older, severely disabled, or victims of wildfire and other disasters may transfer their existing low assessed value to a replacement primary residence in California, within limits, valuable for a longtime owner downsizing into a Wilshire Corridor or Century City condo who would otherwise reset to a much higher basis. Prop 19 also narrowed the old parent-to-child exclusion, so inherited property is more likely to be reassessed than before. These rules are fact-specific and change; treat them as a reason to call a tax professional early, not a plan you finalize from an article.

Verify the numbers before you write an offer

The county tax bill and preliminary title report show exactly what a parcel pays, including extra line items such as Mello-Roos special taxes in newer master-planned districts. Before you write an offer, pull the actual bill, estimate your reassessed amount from your purchase price and the combined rate, budget for the supplemental bill, and check anything ULA-related if you are shopping at the high end. For current pricing across LA condo neighborhoods, our market report at /market-stats carries the live numbers; for how a bill lands on a specific unit, your escrow officer and a tax professional are the right guides.