Why would two homes, both carrying a "Beverly Hills, CA 90210" mailing address, walk away from closing with a tax bill that differs by hundreds of thousands of dollars? The answer has nothing to do with square footage, lot size, or which side of Sunset feels more prestigious. It comes down to a boundary drawn in 1914 that most buyers never think to check.
Beverly Hills the incorporated city is fully exempt from Measure ULA, the Los Angeles transfer tax that everyone in this market has learned to call the mansion tax. But a large stretch of hillside carrying that same 90210 zip code, known in the trade as Beverly Hills Post Office or BHPO, is not exempt at all. It sits inside the City of Los Angeles. It gets LA police, LA fire, and LAUSD schools. And on a high-value sale, it gets the full weight of a tax the Flats will never see.
That single jurisdictional fact, not proximity to Rodeo Drive, is the real predictor of a seller's net proceeds in this market right now.
How the same envelope ends up in two different tax systems
When Beverly Hills incorporated in 1914, its northern boundary landed roughly a mile north of Sunset Boulevard. The hillside land stretching further up toward Mulholland Drive stayed part of Los Angeles. In the 1920s, the federal government routed that area's mail through the Beverly Hills post office, and by 1963 it had been folded into the 90210 zip code alongside the city itself. The mail delivery decision stuck. The city line never moved.
The result is a neighborhood that looks and photographs like Beverly Hills, sells under a Beverly Hills address, and pays taxes like Los Angeles. BHPO residents vote in Los Angeles elections, call the LAPD and LAFD for emergency response, and enroll their kids in Los Angeles Unified schools rather than Beverly Hills Unified. On a sale above the ULA thresholds, they also owe the tax that Beverly Hills proper is structurally immune to.
As one Los Angeles luxury agent put it earlier this summer, the tax "has become part of nearly every meaningful conversation we have about timing, pricing, renovation." That conversation looks completely different depending on which side of an invisible line your parcel sits.
What the tax actually costs at today's thresholds
Measure ULA took effect on April 1, 2023, funding affordable housing and tenant protection programs through a transfer tax on high-value property sales inside the City of Los Angeles. The thresholds adjust every July 1 based on the Chained Consumer Price Index, and the current figures, effective for any transaction closing after June 30, 2026, are set by the Los Angeles Office of Finance.
| Sale price | ULA rate | Tax owed |
|---|---|---|
| Below $5,400,000 | 0% | $0 |
| $5,400,000 to $10,899,999 | 4% | $216,000 at the low end |
| $10,900,000 and above | 5.5% | $599,500 at the low end |
The tax applies to the entire gross sale price, not just the amount above the threshold, and it falls on the seller with no exemption for a primary residence. That structure creates a genuine cliff. A property that sells for $5,399,000 owes nothing. The same property closing one dollar higher crosses into a $216,000 bill. Agents working BHPO listings near that line routinely price just under the threshold rather than just above it, because the seller nets more at the lower number than at the higher one once the tax is factored in.
None of this touches a listing inside Beverly Hills city limits. Trousdale Estates, the Flats, and the rest of the incorporated city pay the standard county and city transfer taxes and nothing more.
Same zip code, two different markets
The price data makes the split obvious once you know to look for it. Recent BHPO sales illustrate just how wide the range runs within that single stretch of hillside, from a $6.4 million close on Clear View Drive up to a $35 million sale on Davies Drive, the kind of spread industry analysts describe as the widest disparity of any submarket sharing the 90210 code. Meanwhile Beverly Hills proper, the incorporated city, posted a single-family median sold price near $5.62 million as of May 2026, according to CRMLS data cited by local market analysts, with Trousdale Estates running roughly 25 to 30 percent above that median through the first quarter of the year.
Cash plays an outsized role in absorbing the tax hit at the top of the market. Estimates on exactly how large a role vary by source and by price tier, ranging from roughly 41 percent of Beverly Hills single-family closings in early 2026 up to figures as high as 65 to 70 percent citywide and 85 to 90 percent in the $10 million-plus trophy tier. Whatever the precise number, the pattern is consistent: the buyers least affected by financing costs are also the ones most willing to absorb a six-figure transfer tax to secure a specific address, and that willingness concentrates disproportionately inside the exempt city limits rather than in BHPO.
Why capital keeps flowing into the exempt side of the line
Industry tracking of transaction volume since ULA's 2023 implementation shows sales above $5 million inside LA City neighborhoods like Bel Air, Holmby Hills, and Brentwood down roughly 38 percent, alongside a near halt in new spec-mansion construction within city limits. Research from UCLA has separately estimated that the tax reduced the likelihood of a given Los Angeles property selling above $5 million by roughly 55 percent.
Beverly Hills proper has been the structural beneficiary of that hesitation. As sellers and developers in LA City neighborhoods delay listing or pull back on new builds, capital that would have transacted there has migrated toward the tax-exempt side of the boundary. That migration shows up in the numbers: the median sale price of a home in Beverly Hills ran $6.1 million over the three months ending in May 2026, up 56.2 percent from the same period a year earlier, with homes selling in an average of 51 days. A jump of that size in a single year is not simply demand for Beverly Hills the brand. It is demand for Beverly Hills the tax jurisdiction.
The ballot fight that could have changed everything, and didn't
For much of the first half of 2026, this entire boundary line looked like it might become irrelevant. The Howard Jarvis Taxpayers Association qualified a statewide ballot measure, the Local Taxpayer Protection Act, for the November 2026 ballot in May, aimed squarely at Measure ULA. The measure would have capped municipal transfer taxes across California at 0.05 percent of sale price, a reduction that would have cut the tax on a $10 million Los Angeles sale from roughly $550,000 to about $5,000.
State lawmakers pushed back with a competing proposal, Assembly Bill 736, that would have capped most local transfer taxes at 1.5 percent statewide, with a higher allowance for a handful of cities like San Francisco and Culver City that already exceed that rate, while still cutting into Measure ULA's own 4 and 5.5 percent brackets. For a few tense weeks in late June, the Howard Jarvis Taxpayers Association publicly refused to withdraw its measure. Then, in a deal struck with state lawmakers in the final days of June 2026, the association pulled its transfer-tax measure from the ballot entirely. Voters this November will instead weigh a narrower constitutional amendment raising the vote threshold for future local special taxes, not a direct cap on the rates Measure ULA already charges.
As of this writing in August 2026, that means the exemption structure driving the BHPO divide is not going anywhere before the November election, and quite possibly not after it either. The line on the map remains the operative fact for anyone pricing a sale this year.
What this means if you are comparing homes
A 90210 zip code tells you almost nothing about a property's tax exposure. Confirming which municipality actually governs a parcel, before you set a list price or model net proceeds, is not optional due diligence. It is the single most consequential fact in a high-value Westside transaction, more consequential than the difference between a renovated kitchen and a dated one.
If you are selling a home near BHPO's upper price tiers, a few thousand dollars of list price can be the difference between a clean sale and a six-figure tax bill. If you are buying, understanding which side of the line a property sits on tells you something real about school district, emergency response, and permitting authority, not just the tax question.
FAQ
Does Measure ULA apply to homes inside the City of Beverly Hills? No. Beverly Hills is an independent, self-governing municipality with its own transfer tax rules, and properties within its city limits are not subject to Measure ULA regardless of sale price.
If my home has a Beverly Hills mailing address, does that mean I'm exempt? Not necessarily. A Beverly Hills, CA 90210 address only tells you which post office handles your mail. Properties in the BHPO area carry that same address while sitting legally inside the City of Los Angeles, which means they are fully subject to the tax.
How do I find out which jurisdiction my property is actually in? The mailing address will not tell you. Confirming legal jurisdiction requires checking the parcel against Los Angeles city and county boundary records, something worth doing before you set a list price or make an offer near the ULA thresholds.
Could this tax go away soon? As of August 2026, no statewide measure currently heading to voters would directly repeal or cap Measure ULA's rates. The measure that had targeted it was withdrawn from the November ballot after a legislative deal in late June.
Understanding which side of a boundary line your property sits on is exactly the kind of detail that separates a confident pricing strategy from a costly surprise at closing. If you are weighing a sale or purchase anywhere near this jurisdictional line in Beverly Hills, BHPO, or the surrounding Westside, Sam & Rudi can walk through the specifics with you. Schedule a Private Consultation to get a clear read on where your property actually stands.
