New York operates a fragmented appeal system with sharply different calendars upstate vs. NYC. NYC properties appeal to the Tax Commission with a March 1 (Class 1) or March 15 (Classes 2-4) deadline. Upstate, almost every assessing unit holds Grievance Day on the fourth Tuesday of May. Tax Certiorari proceedings (Article 7) must be filed in Supreme Court by the day taxable status is final — typically July or earlier. Long Island operates on its own schedule (Nassau and Suffolk).
Verify before filing. Statutory deadlines change, and many counties operate on their own schedule inside the state framework. Always confirm the current year's window with the assessor or appeal board for the specific jurisdiction before relying on a date.
State-level deadlines plus major sub-jurisdictions where the schedule diverges from the state default. Where a column says "Varies," confirm the date with the local assessor.
| Month | Type | Event | Date | Details |
|---|---|---|---|---|
| January | RP | NYC Tentative Assessment Roll published NYC |
January 15 | Department of Finance publishes tentative roll. Triggers NYC appeal window. |
| March | RP | NYC Tax Commission appeal — Class 1 NYC |
March 15 | Deadline for Class 1 (1-3 family residential) appeals to the NYC Tax Commission. |
| March | RP | NYC Tax Commission appeal — Classes 2/3/4 NYC |
March 1 | Deadline for Class 2 (apartments), Class 3 (utilities), and Class 4 (commercial) NYC Tax Commission appeals. |
| March | RP | Nassau County appeal deadline (AROW) Nassau County |
March 1 (typical) | Nassau Assessment Review Commission grievance period. Window typically January 2 through March 1 — verify each cycle. |
| May | RP | Tentative roll filed (most upstate) |
May 1 | Most non-NYC, non-Nassau assessing units file tentative assessment rolls May 1. |
| May | RP | Suffolk County Grievance Day Suffolk County towns |
Third Tuesday in May | Suffolk towns hold Grievance Day on the third Tuesday of May (one week earlier than the rest of upstate). |
| May | RP | Statewide Grievance Day |
Fourth Tuesday in May | Standard Grievance Day for assessing units across NY State (excluding NYC, Nassau, and Suffolk towns). |
| July | RP | Final assessment roll filed |
July 1 (most jurisdictions) | Triggers the 30-day window to file Article 7 (Tax Certiorari) proceedings in NY Supreme Court. |
| December | RP | Appeal Deadline Buffalo (Erie County) |
31-Dec | City of Buffalo deadline |
| February | RP | Appeal Deadline Rochester (Monroe County) |
Mar | City of Rochester deadline |
| August | RP | Appeal Deadline Oneida County |
Aug | City of Utica deadline |
| July | RP | Appeal Deadline Oneida County |
Aug | City of Rome deadline |
| January | RP | Appeal Deadline Syracuse (Onondaga County) |
Jan | City of Syracuse deadline |
| January | RP | Village Appeal Deadline Westchester County |
Feb | Village deadlines in February |
| January | RP | Town Appeal Deadline Westchester County |
Jun | Most town deadlines are 3rd Tuesday in June |
| January | RP | Appeal Deadline Westchester County |
Jan | City of White Plains deadline |
| October | RP | Appeal Deadline Westchester County |
Nov | City of Yonkers deadline |
RP = Real Property · BPP = Business Personal Property · Both = Applies to both
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