But that wasn’t the reaction to the publication of a supplemental roll by the DOF a “rich tax” dragnet, a doxxing operation, a “hit list.” Citadel’s Ken Griffin said he felt doxxed and called New York City Mayor Zohran Mamdani’s April video, filmed outside his own $238 million Central Park South penthouse, a “dangerous” stunt—even though his purchase price, city valuation, and ownership have sat in the same public files for years. Nothing in the file was secret.

The DOF took two things it already tracks separately: assessed value, and which properties might not be a primary residence, and put them in one spreadsheet. Combining two already-public columns on an Excel file isn’t a breach. But the uproar does reveal a lot about the supposed socialist takeover of New York City.

What’s the hubbub about?

On July 24, DOF posted two new files to its property assessments page: a supplemental roll for Tax Class 1 (with 684,619 properties) and one for Tax Class 2 (275,091 properties), making a 959,710 combined, a subset of the city’s full 1,048,576-row assessment roll across Classes 1 through 4. The city was legally required to publish the files by July 25 ahead of the tax’s implementation. The only new thing to the public realm is the imputed valuations for roughly 36,700 individual co-op units, almost all in Manhattan, which is data the DOF has never published before, since co-ops are normally assessed at the building level. (Most of these co-ops don’t clear the thresholds for pied-à-terre tax and therefore are not included in Fortune’s analysis).

When this native New Yorker and avid ACRIS user (the city’s automated City Register that let’s you search property records) went through the new supplemental roll, it quickly became apparent why there was so much public outcry and confusion surrounding the tax.

For starters, neither file is filtered beyond building classification code. (Some coverage seized on that, pointing to modest homes on Chaffee Avenue in Throggs Neck and Challenger Drive on Staten Island as proof the list swept up working-class New Yorkers). The unfiltered file also caught properties that plainly wouldn’t qualify: the embassies of Italy (worth $52.5 million at 690 Park Avenue), Indonesia (worth $57.7 million at 5 East 68th Street), and the UAE (worth $51.6 million at 39 East 74th Street), plus large LLC-held trophy properties all wouldn’t be subject to the tax. Reporters found DOF Commissioner Richard Lee’s own Flushing home and a Park Slope rowhouse owned by former Mayor Bill de Blasio in the same unfiltered file, alongside Griffin, Joe Tsai, Anna Wintour, Woody Allen, Martin Scorsese, and Spike Lee, but none of which means they owe the tax, since the file was never filtered by residency.

Once the thresholds are applied, the numbers outside Manhattan and Brooklyn drop fast: our own count found only 77 in the Bronx and 23 on Staten Island, out of roughly 24,300 citywide. One widely cited figure put the “real” list at 31,000, but per an independent analysis by newsletter writer Tom Flaschen, that requires counting roughly 7,200 entire co-op buildings valued over $1 million as single taxable properties and co-ops are taxed apartment by apartment. Corrected, the number lands close to 24,300.

A scandal of undervaluation, not overreach

Some of the loudest complaints centered on high-value properties sitting inside LLCs and trusts, as though the roll had cracked open a hidden vault. People use these structures for liability protection and estate planning: they’ve been paying property taxes on these units for years, so the DOF has always known what they own. (That’s because New York’s 2019 LLC Transparency Act requires LLCs holding residential real estate to disclose their beneficial owners on any transfer after September 2019). Of the roughly 24,300 properties on the supplemental list that actually clear the tax’s thresholds, about 9,458 (39%) are held through entities, and 61% sit in an identifiable person’s name, a majority-named list, hiding in plain sight. Scanning it for anyone actually famous is thin: a scattering of full-time New Yorkers holding property under their own name, plus a short roster of recognizable trusts, is the extent of the “hit list.”

Once the thresholds are applied, the numbers outside Manhattan and Brooklyn drop fast: our own count found only 77 in the Bronx and 23 on Staten Island, out of roughly 24,300 citywide. One widely cited figure put the “real” list at 31,000, but per an independent analysis by newsletter writer Tom Flaschen, that requires counting roughly 7,200 entire co-op buildings valued over $1 million as single taxable properties — wrong, since co-ops are taxed apartment by apartment. Corrected, the number lands close to 24,300.

The tax itself: Mamdani and Governor Kathy Hochul first floated it in April at a flat $5 million threshold. The version that passed the state legislature on May 27, 2026, signed by Hochul the next day, is more granular: 0.8%–1.3% on one- to three-family homes over $5 million, 4%–6.5% on condos/co-ops over $1 million (4% from $1M–$3M, 5.25% from $3M–$5M, 6.5% above). Estimates on scope ranged from Hochul’s 13,000 units to Comptroller Mark Levine’s roughly 11,000 (515 co-ops). Projected revenue: about $500 million a year. The city added 13 new DOF positions and 11 at the Office of Administrative Tax Appeals.

Stripped of the panic: neither half of this is (or should be) a story. The DOF’s records have been public since 1830. Second, the tax is a modest surcharge on a bill these owners already pay: for the average home clearing the $5 million threshold, just 0.8% on top. Using Griffin as the test case: his current tax bill on the Central Park South penthouse is $858,332 for 2026-2027; under the surcharge, it rises to roughly $1.87 million, more than double, but on a $238 million apartment.

What is more of a scandal, though, is the DOF’s assessment system, which does the wealthy more favors than the outrage cycle credits. City assessments on luxury properties can run at 10% or less of true market value. That’s how Griffin’s $238 million penthouse ends up on the books at $15.5 million. “They have assessed this value on properties at much lower value, but the rate is much higher,” said Denisse Moderski, a state and local tax partner at PKF O’Connor Davies. “You have to look at it from both angles: what value are they using, but then a higher rate—does this offset?”

She said she expects the city to close the gap eventually: “I can’t imagine that the city would not come out with some adjustment to catch up on that.” That undervaluation problem predates this tax by years, and it means the surcharge will keep raising less than the rates alone suggest.

The self-described socialist mayor and the actual wealth tax already in place from his competitor

The city added 13 new DOF positions and 11 at the Office of Administrative Tax Appeals to deal with the incoming barrage of letters they expect to receive, and that’s partially due to a botched rollout that seems to be typical of Mamdani’s administration, now more than half a year into the role.

In late July, the DOF began mailing notification letters to roughly 17,000 owners it believes may be subject to the surcharge, a small fraction of the 959,710 properties on the published list, but enough to catch full-time New Yorkers by surprise. City Council Member Gale Brewer said the Upper West Side home she’s lived in since 1994 was flagged: “I’m still confused.” At a Wednesday press conference, Mamdani and Lee defended the process. “The tax property roll that was posted last week is a reflection of all properties across New York City, not a reflection of those, specifically, that the pied-à-terre tax will be levied upon,” Mamdani said.

Instead, Lee directed comments at the public backlash. “The misconception that it is a targeted specific list of those impacted by the non-primary resident surcharge is false.” Lee added that some longtime owners are getting letters because properties sit in trusts or LLCs, or records are outdated, and said DOF is proactively reaching out to co-op owners given how much more complicated their ownership structure makes the tax to administer.

The botched rollout of the letters has gotten the greatest amount of ire from New Yorkers: why are people’s only homes listed in the supplemental roll; why are homes clearly below the thresholds included at all?

For a self-described socialist, the tax policy is anything but, and pales in comparison to the very man who ran to the right of him twice—and lost twice.

In 2021, before he resigned, then-Governor Andrew Cuomo raised the state income tax rate nearly a full point on households earning over $2 million, adding brackets above $5 million and pushing the top rate to 10.9%. That increase is a major reason the state now sits on close to $15 billion in cash reserves. Cuomo also expanded New York’s mansion tax (a tax on properties valued at over $1 million) in 2019, turning a flat 1% transfer tax, in place since 1989, into a progressive structure up to 3.9% on sales above $25 million, and it was dedicated to MTA capital improvements and estimated to pull in roughly $400 million a year. While that was a one-time charge instead of this tax’s proposed annual fees, set against either, a surcharge raising about $500 million from roughly 24,300 properties isn’t radical. It’s arguably the least novel tax increase on the wealthy New York has passed in five years. In fact, Cuomo only hiked the mansion tax after dropping his initial plan: a pied-à-terre levy.

A botched rollout

In a press conference this week explaining the rollout and addressing the backlash, Mamdani said it was intentional: “The reason that we wanted to conduct outreach months in advance… would be to ensure that that exact premise would be fulfilled.” However, many homeowners who have called their only residence home for years are wondering if this all could have been skipped, or if the city could have better conducted the roll out to genuinely hit only non-primary residences above the threshold pay. Regardless, a DOF spokesperson said the 17,000 figure could shrink as more owners verify residency.

New York isn’t inventing a new tax category, it’s actually late to one other cities have tested. Vancouver has run a vacancy or speculation tax since 2016, now a 3% municipal Empty Homes Tax atop a provincial tax as high as 3% for foreign owners, a combined bill that can hit $75,000 on a $1.5 million vacant unit. Toronto’s Vacant Home Tax, launched 2022, is now 3% of assessed value. Singapore charges foreign buyers a flat 60% stamp duty at purchase rather than an annual holding tax. Hawaii County adopted a surcharge this year on non-owner-occupied homes over $4 million, expected to raise about $94 million.

San Francisco is the cautionary tale, and the reasons it failed don’t apply here. California’s Proposition 13 caps the statewide property tax rate at 1% of assessed value—a constitutional ceiling that’s why San Francisco couldn’t just add a percentage surcharge the way New York did. So when voters passed Proposition M in 2022, the city built a flat per-unit fee instead: $2,500–$20,000, escalating the longer a unit in a 3+ unit building sat vacant past 182 days. A San Francisco Superior Court judge struck it down in October 2024—an unlawful taking under the Fifth Amendment, since the fee functioned as coercion to force renting rather than revenue collection; a violation of California’s Ellis Act, which bars penalizing owners for not renting; and a due process and privacy violation, since it also burdened letting family use a property instead.

New York’s tax doesn’t punish a choice—it doesn’t ask whether an owner rented a unit out or left it empty. It asks a passive question: is this your primary residence. That’s a status-based surcharge, not a penalty for behavior, layered onto the existing property tax system, exactly the design Prop 13 forced San Francisco to abandon. New York has no equivalent to the Ellis Act, but it also doesn’t need one, since the fact pattern that made SF’s fee look coercive isn’t present here.