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Has anywhere actually voted to tax the rich — and gone through with it?

Yes. In May 2026, New York state lawmakers passed Mayor Zohran Mamdani's pied-à-terre tax — an annual levy on high-value second homes in the city, expected to raise around $500 million a year. His larger plan, a 2% income tax on earnings over $1 million, is still being fought over in Albany.

$500m
expected annual revenue from New York's new tax on luxury second homes, passed May 2026 — CNBC / NYC Mayor's Office
New York started actually taxing the rich: Mayor Mamdani's pied-à-terre tax passed in May 2026 — an annual tax on high-value second homes expected to raise $500 million a year. Billionaire Ken Griffin's penthouse tax bill roughly quadruples, and Manhattan luxury sales held firm anyway.
New York's pied-à-terre tax — proposed, passed, and in force

Zohran Mamdani won the New York mayoralty campaigning explicitly on taxing the rich, took office in January 2026 facing a historic $12 billion budget gap, and within five months had his first wealth-targeting tax through the state legislature. The pied-à-terre tax, passed by Albany lawmakers in May 2026, is an annual levy on high-value second homes in New York City — properties owned by people whose primary residence is somewhere else.

The design is deliberately targeted. It touches nobody's primary home. In its first phase it applies to non-primary condos and co-ops assessed at over $1 million, at rates from 4% to 6.5% of assessed value; from 2028 the city moves to market-based valuations with rates of 0.8% to 1.3% on properties worth over $5 million. It is expected to raise around $500 million a year for a city budget that funds schools, transit and housing.

The predictable threats followed. Citadel CEO Ken Griffin — whose $238 million Central Park penthouse had been taxed on a city valuation of just $15.5 million — became the public face of opposition after Mamdani announced the tax in a video outside his building, and threatened to move jobs to Miami. Griffin's Manhattan property tax bill roughly quadruples to around $4 million a year. Yet by July 2026, CNBC reported that Manhattan luxury real-estate sales were holding firm despite fears of a 'Mamdani effect'.

This page matters for Britain because it breaks the fatalism. The standard argument against taxing wealth is that no one dares and it can't be done. New York — the world's densest concentration of financial wealth — just did it, through the ordinary democratic process, and the sky has not fallen. The bigger test, Mamdani's proposed 2% income tax on New Yorkers earning over $1 million, is still being fought in Albany. But the first domino has actually fallen.

Common questions

Did this actually pass, or is it just a proposal?
It passed. Mamdani and Governor Hochul announced the proposal in April 2026, and state lawmakers passed it in late May 2026. CNBC published a breakdown of who pays and how much on 28 May 2026.
Doesn't this just hit ordinary people with a second flat?
No. It applies only to non-primary residences above a $1 million assessed value in phase one, and above a $5 million market value once revaluation kicks in from 2028 — luxury pieds-à-terre, most of them owned by people who do not pay New York income tax because they live elsewhere.
Did the rich flee New York?
Not so far. CNBC reported in July 2026 that Manhattan luxury property sales held firm despite predictions of a 'Mamdani effect'. Ken Griffin — the loudest objector — was already a tax resident of Florida before the tax existed.
What about his bigger tax-the-rich plan?
Mamdani's flagship proposal — a 2% city income tax on earnings above $1 million — needs approval from the state legislature in Albany, and that fight is ongoing. The pied-à-terre tax was the first, fastest win.

Sources — check them yourself