Property Tax Grievances in Nassau, Suffolk and Westchester: Deadlines
When and how to grieve a property assessment in Nassau, Suffolk and Westchester, from Nassau’s March deadline to Grievance Day, and small claims review.
By Seayora Editorial Team · Published · Facts checked · 3 min read
Short answer: Outside New York City, a homeowner challenges an assessment by filing a grievance with the assessing unit, and the deadlines are local. In Nassau County, appeals go to the Assessment Review Commission, due March 1, 2027 for the 2028/29 roll. In most Suffolk towns Grievance Day is the third Tuesday in May, and in most Westchester towns the third Tuesday in June. An owner-occupied one- to three-family home can then go to small claims assessment review for $30.
Key takeaways
- Nassau County: file with the Assessment Review Commission between January 4 and March 1, 2027 for the 2028/29 assessment.
- Suffolk County towns: Grievance Day is the third Tuesday in May; it was May 19, 2026.
- Westchester: most towns use the third Tuesday in June (June 16, 2026); several cities run their own calendars.
- Small claims assessment review costs $30 and must be filed within 30 days after the final roll is filed.
Who decides a property tax grievance outside NYC?
Each assessing unit has a board of assessment review that hears complaints. Under RPTL § 512, in a town it meets starting the fourth Tuesday in May unless a city charter, county charter, county tax act or special law sets another date, which is why Long Island and Westchester follow their own calendars. Most complaints are filed on Form RP-524, and a complaint must be received by the deadline, not just postmarked.
When are the deadlines?
| Where | Who hears it | Deadline |
|---|---|---|
| Nassau County | Assessment Review Commission | Roll published January 4, 2027; appeals for 2028/29 due March 1, 2027 |
| Suffolk County towns | Town board of assessment review | Grievance Day, the third Tuesday in May (May 19, 2026) |
| Most Westchester towns | Town board of assessment review | Grievance Day, the third Tuesday in June (June 16, 2026) |
| New York City | NYC Tax Commission | March 15 for class 1, March 1 for other classes |
In Nassau, the Assessment Review Commission extended the filing deadline for the 2027/28 roll to March 31, 2026, so deadlines can move; check the ARC calendar each year (Nassau County ARC). In Suffolk, the town filing period ends on Grievance Day (Town of Babylon; Farrell Fritz). In Westchester, a law firm count found 22 of 30 assessing units shared the June 16, 2026 date, with cities such as New Rochelle, White Plains and Yonkers on their own schedules (Farrell Fritz); Greenburgh, for example, accepts grievances from June 1 to the third Tuesday in June (Town of Greenburgh).
What if the board denies your grievance?
Owners of a one-, two- or three-family owner-occupied home used only as a residence can file for small claims assessment review (SCAR) under RPTL § 730. You must first have filed a grievance with the board. The petition is due within 30 days after the final assessment roll is completed and filed, or by October 25 in a city of one million or more, and the fee is $30. Other owners, including investors and commercial owners, go to state Supreme Court in a tax certiorari proceeding.
How do you build a strong grievance?
- Find your assessment and the equalization rate, and convert the assessment to the market value the town is claiming.
- Compare it with recent sales of similar homes nearby, or with an appraisal.
- Check the property record for errors: square footage, bathrooms, a finished basement that is not finished.
- File the complaint on time with the right body; a village with its own assessment roll needs a separate grievance.
Inside the city the process and the classes are different; see NYC property tax classes and rates.
Frequently asked questions
When is Grievance Day in Suffolk County?
In Suffolk’s towns it is the third Tuesday in May; in 2026 it was May 19. Villages with their own assessments have separate dates.
What is the deadline to appeal a Nassau County assessment?
For the 2028/29 assessment, the Assessment Review Commission’s filing period runs from January 4 to March 1, 2027. The commission has extended deadlines before, so check its calendar.
How much does small claims assessment review cost in New York?
$30 per petition. It is available to owner-occupied one- to three-family homes after a grievance has been filed with the board of assessment review.
Sources
- N.Y. Real Property Tax Law § 512, Meetings of board of assessment review, New York State Senate
- Form RP-524, Complaint on Real Property Assessment, New York State Department of Taxation and Finance
- Assessment Review Commission, Nassau County
- Assessment Review Commission calendar, Nassau County
- Grievance Day, Town of Babylon
- Suffolk County filing period for real property tax grievances begins May 1, 2026, Farrell Fritz, P.C.
- Majority of Westchester property owners face June 16, 2026 tax appeal deadline, Farrell Fritz, P.C. (via Mondaq)
- Assessment calendar, Town of Greenburgh
- N.Y. Real Property Tax Law § 730, Small claims assessment review, New York State Senate
How Seayora helps
Property tax center: Keep each property’s assessments, grievances and outcomes with its tax records.
This article is general information, not tax advice. Tax rules change and your situation is your own, so confirm the treatment with a CPA or enrolled agent before you file.
How we write and check these guides: editorial standards.
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