Mamdani's Second Housing Tax Sent to Court

The implementation process of the 'pied-à-terre' tax that New York City Mayor Zohran Mamdani's administration has enacted on luxury second homes has been taken to court. A judge in Staten Island ordered the cancellation of the existing notices sent by the city administration to property owners and the re‑execution of the process.

The court also demanded the removal of the online list that contains hundreds of thousands of properties and has sparked public debate. However, the decision does not invalidate the tax itself; the court's objection focuses on how the tax is applied. New York's administration, on the other hand, invoked the legal process that halted the implementation by appealing the ruling.

Court: The process was conducted incorrectly.

Judge Wayne Ozzi of the Richmond County State Supreme Court criticized the implementation process of the New York City Finance Department in his ruling issued on September 29.

According to the court, the city administration sent notices without individually determining which homes were truly second residences and forced property owners to prove that their houses were their primary residences.

Ozzi ruled that the failure to use the data in the Finance Department's possession imposed an unnecessary burden of proof on thousands of homeowners. The court called for the cancellation of the previously sent notices and for new notices to be issued only after the necessary investigations had been conducted.

Approximately 17,000 property owners were notified

The city administration had sent notifications in July to about 17,000 property owners, indicating that their properties might fall under the new tax

However, as the process progressed, it emerged that some recipients of the notifications actually lived continuously in those houses and should not have been subject to the second residential tax. It was also reported that the city administration had not checked the property owners' income tax records before sending the initial notifications

A group of homeowners filed a lawsuit against the city administration. The plaintiffs argued that the notifications sent to them did not meet legal requirements and that property owners were being unnecessarily threatened with tax

The list containing hundreds of thousands of properties will be removed

Another issue the court focused on was the comprehensive property list published by the city administration online

Plaintiffs argued that the list, covering more than 900,000 properties, made the owners' names and addresses publicly available. Judge Ozzi ordered the removal of the list from the website and the adoption of the properties that were actually determined to fall under the additional tax instead.

New notices must also clearly explain how property owners can appeal the municipality's decision and provide records that support the Treasury Department's assessment.

The tax targets luxury second homes.

The regulation known as a “pied‑à‑terre” foresees an additional tax on high‑value homes in New York that are not the owner's primary residence.

The tax took effect on July 1, 2026. Under the regulation, second homes above certain value thresholds are targeted, while separate thresholds apply to condo and co‑op properties. City officials expect the measure to generate roughly $500 million a year.

Mamdani administration argues that the core purpose of the measure is to raise more revenue from affluent property owners in New York who own expensive homes but do not use them as their primary residence.

The city administration appealed the ruling.

The court ruling does not mean the tax has been entirely abolished. The judge decided on the municipality's implementation process rather than on whether the tax is lawful in this case.

New York administration filed an appeal after the ruling. According to Reuters, the appeal set in motion a process that temporarily halted the enforcement of the court decision. Thus, the legal battle over the second‑home tax moved to a new phase.

The Mamdani administration also continues to defend the tax. City Hall spokesperson Matt Rauschenbach said the regulation is intended to make luxury second‑home owners contribute more to city services, and declared that they do not accept the court ruling.

Meanwhile, separate lawsuits targeting the tax itself are also ongoing. Property owners, including former U.S. Trade Secretary Wilbur Ross and businessman Steve Wynn, have filed a separate lawsuit against the regulation's constitutional and legal foundations.

Therefore, the future of New York's second‑home tax will be shaped by both the municipality's appeal of the final ruling and the outcome of other lawsuits that target the tax itself.