The emergency rule that carries the extension

On August 1, 2026 the Mayor and the Department of Finance Commissioner announced the extension. The instrument implementing it was signed by Commissioner Lee on July 31, 2026, approved by Mayor Mamdani, and took effect August 3, 2026, amending 19 RCNY 62-06(b)(1) under the emergency procedures of section 1043(i)(1) of the City Charter.

What did the amendment change?

• The window, for this year. For fiscal year 2026-27 an appeal of an initial determination may be filed no later than September 18, 2026, or a date the Commissioner of Finance selects where good cause is shown, whichever is later.
• Where may a filing be made? In-person filing at locations the Commissioner designates is now authorized alongside the electronic portal, which had been the only route.
• The base evidence set, relaxed. One of the most recent income tax return showing the address or a driver's license or other DMV-issued identification now carries it. If neither exists, the fallback is a voter identification card together with one other proof that the property is the primary residence.

What should an owner do with the good-cause valve?

Work to September 18, 2026, and treat the valve as though it does not exist. The rule makes that date a floor rather than a wall, but the later date is one the Commissioner selects on a showing of good cause, case by case. It is not an extension anyone is entitled to, and no owner can plan around a discretion that has not been exercised.

Why is this rule temporary?

An emergency rule adopted under Charter 1043(i)(1) runs 60 days and may be renewed once for another 60, which carries this one past the September 18 deadline it created. The Department of Finance is expected to bring a permanent rule through ordinary rulemaking in the meantime, with a comment period. This record will carry that proposal when it is published.