How to appeal your property tax value in New York

4 sourced points for New York, each linked to the official page it comes from.

Outside New York City and Nassau County, grieve your assessment on Form RP-524, Complaint on Real Property Assessment. File it with the assessor or the board of assessment review (BAR) in your city or town. It's free and you don't need a lawyer. tax.ny.govOct 21
If your village assesses property, you have two assessments. To grieve both, file a separate RP-524 with the town and with the village. tax.ny.govOct 21
A mailed form must reach the assessor or BAR by grievance day. Miss the deadline and you lose both the administrative and court review of your assessment for that year. tax.ny.govOct 21
If you disagree with the BAR, you can use small claims assessment review (SCAR) for a $30 fee if you live in your one, two or three family home, or bring a tax certiorari case in state supreme court. Either must start within 30 days of the filing of the final assessment roll or notice of it. tax.ny.govOct 21

The dates

Date and source	Deadline	Applies to
Varies, see rule set by noticetax.ny.govOct 21	Appeal deadline Grievance Day: file your assessment complaint File Form RP-524 with the Board of Assessment Review. It's the fourth Tuesday in May in most places. Cities and towns that share an assessor can pick a day from the fourth Tuesday in May to the second Tuesday in June. Villages and cities set their own dates. Check with your assessor.	All 54 New York counties except Bronx, Kings, New York, Queens, Richmond, Nassau, Suffolk, Westchester