The Line Through 90210 That Can Cost a Seller Seven Figures
Two weeks ago, a developer named Ramtin Ray Nosrati listed a spec mansion on Donhill Drive for $35 million. The listing carries a Beverly Hills mailing address and the famous 90210 ZIP code. It is not, technically, in Beverly Hills. Donhill Drive sits in the section of Los Angeles known as Beverly Hills Post Office, and, as Hoodline reports, that single fact means the sale carries a Measure ULA tax bill of roughly $1.9 million that a neighbor two streets south, inside the actual city limits, would never see.
That gap is not a rounding error or a fee buried in escrow paperwork. It is the entire ballgame for anyone shopping or selling above a few million dollars in this part of Los Angeles, and it has nothing to do with the house. It has to do with a municipal boundary that the postal address does not reflect.
Beverly Hills Post Office, usually shortened to BHPO, refers to the hillside neighborhoods north of Sunset Boulevard that share the Beverly Hills post office and the 90210 ZIP code but sit inside the City of Los Angeles rather than the incorporated City of Beverly Hills. The distinction dates back to the 1920s, when the federal government assigned Beverly Hills postal service to a then-rural stretch of the Santa Monica Mountains. The neighborhood kept growing. The city line never moved to catch up.
For most of that history, the boundary was a curiosity. It decided which police department responded to a call and which building department reviewed a remodel permit. Then, as Hanson Bridgett reports, Los Angeles voters passed Measure ULA in November 2022, a transfer tax on high-value real estate sales that took effect the following April, and the boundary stopped being a curiosity. It became one of the largest single variables in a Westside real estate transaction.
Trousdale Estates shows the other side of that line. The 410-acre hillside enclave above Sunset was subdivided by developer Paul Trousdale starting in 1955 on former Doheny Ranch land, and it holds one of the largest concentrations of custom mid-century architecture anywhere in Los Angeles, with homes by A. Quincy Jones, Paul R. Williams, Wallace Neff and Cliff May kept low by a 1987 ordinance capping every structure at fourteen feet. Trousdale sits inside the actual City of Beverly Hills. A sale there, no matter the price, owes no Measure ULA tax at all.
Same ZIP code. Same postal city on the envelope. Two entirely different tax outcomes at the closing table.
The City of Los Angeles adjusts its Measure ULA thresholds annually for inflation. Effective for sales closing after June 30, 2026, the top rate applies to:
| Sale price | Tax rate |
|---|---|
| $10,900,000 and above | 5.5% |
The Los Angeles County Registrar-Recorder lists the standard documentary transfer taxes that, inside the City of Los Angeles, combine to roughly 0.56 percent on top of Measure ULA. Sell a home for $10 million in the City of Los Angeles and Measure ULA alone runs $400,000.
Beverly Hills is where the exemption runs directly against a shared ZIP code and a shared postal identity, which is exactly why the Donhill Drive example matters more than a generic Westside comparison would. Two houses can look identical in a listing search and diverge by seven figures the moment escrow closes.
The jurisdictional line is not the only threshold that behaves like a cliff rather than a slope. Measure ULA's price threshold works the same way. It is not a bracket, where you only pay the higher rate on dollars above the line. It is a gross tax on the entire sale price the moment you cross it.
A City of Los Angeles property that sells for $5,399,999 owes no Measure ULA tax whatsoever. Sellers and their agents who understand this have started pricing and negotiating with real precision around the threshold rather than simply chasing the highest number a buyer might offer.
The tax has changed behavior at scale, not just at the margins. Research from UCLA's Lewis Center found that Measure ULA reduced the odds of a Los Angeles property selling above the $5 million threshold by as much as 55 percent since the tax took effect. Reporting on the tax's first years found that single-family residential sales accounted for roughly 59 percent of the more than $1 billion in Measure ULA revenue collected since April 2023, even though the measure was originally pitched around commercial and institutional transfers.
Some of that suppressed inventory has not disappeared. It has relocated. The Reed Corporation points to a measurable share of high-end listings shifting toward:
Off-market and private-listing strategies have grown alongside this shift. Selling quietly does not erase a Measure ULA obligation if the price crosses the threshold, but it gives a seller more control over timing and negotiation, which matters when a single dollar of final price can swing the tax bill by hundreds of thousands.
None of this is settled for good. A statewide ballot initiative backed by the Howard Jarvis Taxpayers Association is aiming for the November 2026 ballot with the goal of repealing or significantly limiting the tax. Anyone timing a sale or purchase around Measure ULA right now is timing it against a law that could look different by the end of the year.
A 90210 address tells you almost nothing about which side of this line a specific parcel sits on. The only way to know is to check the property's actual municipal jurisdiction against the Los Angeles city boundary, not the ZIP code or the mailing city printed on the listing sheet. That check belongs early in the process, before a buyer falls for a house or a seller sets an asking price, not as a surprise line item during escrow.
For sellers weighing a listing near the $5.4 million or $10.9 million marks, or evaluating whether a BHPO address is really costing what the mailing label suggests, the math is specific enough to model in advance rather than discover at closing. For buyers, the same boundary check changes what a given asking price actually represents in total cost, and it is worth factoring into any offer on a home carrying a Beverly Hills address north of Sunset.
As of May 2026, the Beverly Hills single-family median sold price stood near $5.62 million according to CRMLS data, which puts a meaningful share of the market sitting right on top of these thresholds. That is not a market where the address on the envelope should do the talking.
Can I tell which side of the line a home is on just by looking at the address? No. The only reliable way is to confirm the parcel's legal jurisdiction against the City of Los Angeles boundary map, since ZIP codes and postal cities follow mail routes rather than municipal lines.
Could the November 2026 ballot measure change this? Possibly. A repeal effort is targeting that ballot, and separately the Los Angeles City Council has floated its own carve-outs for new construction and Palisades Fire-affected sellers. Nothing has been decided as of this writing, which is one more reason to get current, address-specific guidance rather than relying on last year's rules.
A boundary line that most buyers never think to ask about can be worth more than the difference between two neighborhoods, two school choices, or two renovation budgets combined. If you are comparing a Beverly Hills-adjacent property this fall, or trying to price a sale near either of these thresholds, Kramer Cruz Group can walk the parcel record with you before you write an offer or set a list price. Schedule a consultation and know exactly which side of the line you are standing on.
This article is general information, not legal, tax or financial advice. Consult a qualified professional about your situation.
Whether you're in the research phase at the beginning of your real estate search or you know exactly what you're looking for, you'll benefit from having a real estate professional by your side. She'd be honored to put her real estate experience to work for you.