If you pay taxes on property you have the right to appeal the property’s annual assessment. This process is popularly called "Tax Grievance". 

There is a new assessment for each year. The time to appeal a new assessment ends before the taxes, based on that assessment, are billed. If you disagree with the most recent assessment, appeal it, even if you are awaiting determination of an appeal you filed last year.

For Nassau County

If you want The Assessment Review Commission (ARC ) to review your property’s assessment, appeal between January 2, 2023 and March 1, Dealine for grieving your taxes in Nassau cuty is March 1, 2023 and you can use this LINK to file online.

• The application requires only basic information about your property. You can file online.
• You are not required to use an attorney. If you hired a representative to challenge a prior assessment, you are free to change representatives or file for yourself for review of the new assessment.
• The Assessment Review Commission may reduce your assessment as appropriate.
• The Assessment Review Commission will never increase the assessment.
• You should decide whether to appeal the new assessment by comparing the Department of Assessment’s adjusted market value with your own estimate of your property’s current market value.
• The Assessment Review Commission may also correct your tax class and hear your appeal if you were denied an exemption.
• There is no fee to file with ARC

For Suffolk County

Deadline for grieving taxes is May 16th, 2023. 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.