What changes next?

Updated 2026-08-25.

The dates still queued, what each one actually does to an owner, and the one date that is not an owner deadline at all.

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

October 6, 2026: the twice-extended application deadline

The exemption application deadline on the July 22 mailing is October 6, 2026, one date for homes, condominiums, and cooperative units. The notices printed August 21 and August 24. On August 1, 2026 the Department of Finance extended the application deadline to September 18 for everyone who received a notice, and its program page now carries October 6. This is the date owners work to.

August 30, 2026: a DOF date, not yours

The transmission date matters for a different reason. Under the rule as adopted, 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, so the transmission date is the start of a clock rather than the end of one. For fiscal year 2026-27 the emergency rule effective August 3, 2026 replaced that window with the later of September 18, 2026 or a date the Commissioner selects for good cause, and the Department of Finance's page now carries October 6, 2026.

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 less settled than the rest. The Tax Commission's Form TC107 of July 15, 2026 has a box for a cooperative dwelling unit, takes one application per unit and lets a cooperative corporation file for a unit owner, so a unit-level route exists, but practitioners still question whether the Tax Commission can take a wave of unit-level disputes, and the legislation does not say how a shareholder disputes a value derived from a building-wide formula.

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 pied-a-terre tax page on mgnyconsulting.com.

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.

Sources

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