What changes next?

The record holds what has happened. This page holds what has not, in order, with what each date changes.

September 18, 2026: the extended response deadline

The response deadline on the July 22 mailing is September 18, 2026, one date for homes, condominiums, and cooperative units. The notices printed August 21 and August 24, and on August 1, 2026 the Department of Finance extended the application deadline for everyone who received a notice. This is the date owners work to.

August 30, 2026: a DOF date, not yours

The transmission date matters for a different reason. An appeal of an initial determination runs 30 days from the date that determination is transmitted, or, if none is transmitted, 30 days after the surcharge appears on the assessment roll. There is no extension and no hardship waiver on that window, so the transmission date is the start of a clock rather than the end of one.

November 2026: bills issued

Bills are issued in November 2026. This is the point at which the surcharge stops being correspondence and becomes an amount on a statement.

December 31, 2026: the final roll addendum

The supplemental market value roll published July 24, 2026 lists properties that may be subject, with Phase One values. A final version is due December 31, 2026. Practitioners have advised owners to check the July list rather than wait for the December one.

January 1, 2027: the first payment

A surcharge that stands first appears on the property tax bill due January 1, 2027, with the second semi-annual property tax installment, and semi-annually after that. In later years the Department of Finance's own notice deadline is January 30.

March 1 and March 15, 2027: the Tax Commission

Value challenges go to the New York City Tax Commission on Form TC107. The deadlines are March 1, 2027 for Class 2 and March 15, 2027 for Class 1, or 30 days after the Department of Finance's final determination, whichever is later.

One piece of that route is unsettled: the Tax Commission has no established procedure for unit-level cooperative valuation protests, and practitioners have flagged it as unresolved.

July 1, 2028: Phase Two

From July 1, 2028, condominiums and cooperatives move to comparable-sales valuation, and a single $5 million threshold with the one- to three-family rate ladder applies. That is a change to how value is set and where the line sits, not a change to the Phase One rates. The mechanics of the comparable-sales method are worked through in the valuation walkthrough on the numbers site.

June 30, 2031: sunset

The surcharge sunsets June 30, 2031, five years after it took effect.

The challenge nobody has filed

Constitutional challenges are expected, on uniformity, Equal Protection, and Commerce Clause grounds. As of July 28, 2026, none is confirmed filed. An expected case is not a pending case, and this record will not report one as the other.