Mayor Zohran Mamdani and Gov. Kathy Hochul’s proposed tax on luxury second homes in the Big Apple will fall far short of its $500 million goal — and drive wealthy residents out of the city, according to the city comptroller’s office.

City Comptroller Mark Levine found that the proposed policy — framed as a needed revenue booster for the city and state — would likely bring in closer to $340-$380 million, over $100 million less than Hochul and Mamdani have claimed.

The tax — which would apply to secondary homes priced a $5 million or more and follow a sliding scale based on assessed value — would target around 13,000 residences, but the comptroller’s audit warned that revenue estimates were based heavily on unknown factors.

Many of the pricey pads are rented to tenants by the owners, which may exclude them from the tax, and it was unclear how the levy would treat homes owned by trusts, LLCs, or family members.

The report, released Thursday, also looked at a similar tax implemented in Vancouver, Canada in 2017 — which resulted in nearly 60% of second home owners selling off their properties to avoid the costly fee as of 2025.  

The comptroller assumes the city could see a similar scramble to sell homes — estimating an around 10% revenue loss.