Grievance Guidelines
https://www.tax.ny.gov/pit/property/contest/grievproced.htm
Any person who pays property taxes can grieve an assessment, including:
Only the assessment on the current tentative assessment roll can be grieved - you can't grieve assessments from prior years.
There is no cost to grieve an assessment and it does not require you to hire a lawyer.
Use Form RP-524, Complaint on Real Property Assessment to grieve your assessment. The form can be completed by yourself or your representative or attorney.
File the grievance form with the assessor or the board of assessment review (BAR) in your city or town.
If your property is located in a village that assesses property, you will have two assessments, one for the village and one for the town. To grieve both assessments, you are required to file a separate Form RP-524 with both the town and village. Grievance dates for villages will vary from towns (see below) - contact your village clerk to determine if your village assesses property and for grievance dates (see below).
For forms, deadlines and instructions, contact the New York City Tax Commission and Nassau County Assessment Review Commission respectively: