What a Nassau tax grievance actually is
Nassau County reassesses every property every year. Each January, the Assessment Department issues a Tentative Assessed Value for the upcoming tax year. If you think that value is higher than what your house would actually sell for, you can grieve it — formally challenge the number with the Assessment Review Commission (ARC).
Filing a grievance does not change your tax rate. It changes the assessed value your rate is multiplied by. A 10% reduction in assessed value translates to roughly a 10% lower property tax bill — and unlike most exemptions, the savings continue every year unless the County reassesses you back up.
You can file on your own (free, using Form RP-524 or Nassau’s online portal) or hire a tax grievance firm. Firms typically charge 50% of the first-year savings on contingency — no savings, no fee.
Key dates for the 2028/29 grievance cycle
- January 2, 2027 — Tentative Assessment Roll published. Your new 2028/29 assessed value is set. Notice arrives in the mail.
- January – March 2027 — Grievance filing window. ARC accepts complaints.
- March 31, 2027 — Deadline to file. Extended from the statutory March 1, 2027.
- By March 31, 2028 — ARC must resolve your challenge by this date (administrative code).
- April 1, 2028 — Final Assessment Roll published. Any settlement reached with ARC is reflected here.
- October 2028 — First bill reflecting the new assessed value (school tax half) arrives.
How to file — the three options
Option 1: File yourself online (free)
Nassau’s Assessment Review Commission accepts grievances through its online portal (AROW). You file Form AR1 (residential) or AR2 (commercial). Required information:
- Your Section, Block, and Lot (SBL) number — find this on your tax bill or via the Nassau Land Records Viewer
- Three to five comparable sales (similar homes nearby that sold in the past 18 months for less than your assessed market value)
- A statement of the value you believe is fair
Filing takes 20-30 minutes. ARC will respond in writing, usually with an offer to settle at a reduced value. If you accept, you sign and you’re done. If you reject, you can pursue Small Claims Assessment Review (SCAR) in NY Supreme Court for ~$30.
Option 2: Hire a tax grievance firm
Firms like Maidenbaum, Heller & Consultants, P.T.R.C., and others handle the entire process. They charge no upfront fee. If they win you a reduction, they take 50% of the first-year tax savings (some advertise 30–40% but verify in writing). If they don’t win, you owe nothing.
Trade-off: you save your time and they have established relationships with ARC. Downside: you give up half of year-one savings and you have to share your contact information.
Option 3: Hire an attorney for SCAR/Article 7
Only worth it for high-value homes ($1.5M+) where the savings justify legal fees. Attorneys handle Small Claims Assessment Review (SCAR, for residences under $450,000 in assessed value) or full tax certiorari proceedings in NY Supreme Court.
DIY vs. grievance firm: which makes sense?
| Factor | DIY (file yourself) | Hire a firm |
|---|---|---|
| Upfront cost | $0 | $0 (contingency) |
| If you win | Keep 100% of savings | Keep ~50% of year-1 savings, 100% after that |
| Time investment | 30 min filing + research | 5 min — sign authorization |
| Best for | Tech-comfortable owners with clear comps | Time-constrained owners, complex cases |
| Risk | None — worst case is no reduction | None — no fee if no savings |
Frequently asked questions
Should I file a Nassau tax grievance every year?
Yes. Nassau reassesses every year, so your assessed value can creep up year over year. Filing a grievance is risk-free — ARC cannot increase your value in response. Most Long Island grievance firms recommend filing annually as a maintenance step.
How much can I expect to save?
Nassau’s historical average for successful grievances is a 5–15% reduction in assessed value, which translates to roughly that same percentage off your tax bill. On the median Nassau home with a $11,129/yr bill, that’s $556-$1,669/yr in ongoing savings. Higher-value homes often see larger absolute savings.
Will ARC raise my assessment if I file?
No. ARC can only reduce or maintain your assessed value during a grievance review. This is a statutory protection. You face zero risk by filing.
Can I grieve if I bought the house recently?
Yes, and you absolutely should. Your purchase price is one of the strongest pieces of evidence available. If you paid less than the assessor’s estimated market value, that gap is a direct argument for a reduction.
What if I miss the March 31, 2027 deadline?
You have to wait until the next cycle (January 2028) to grieve. There is no late-filing window for Nassau grievances. Mark your calendar for the next cycle and set up a reminder for January.
Does grieving affect my STAR exemption or other benefits?
No. STAR, Senior, Veterans, and other exemptions are separate from your assessed value. Grieving reduces the taxable assessed value those exemptions are applied to — typically a net positive.
How long does the process take?
ARC has until March 31, 2028 to resolve 2028/29 grievances. Most cases are resolved by fall 2027. You’ll receive a written settlement offer in the mail. If you accept, the reduction shows up on your October 2028 school tax bill.
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Sources and citations
- NY Tax & Finance — Contest your assessment tax.ny.gov
- NY State Form RP-524 (grievance complaint form) tax.ny.gov
- NY State Form RP-524 — instructions tax.ny.gov
- Nassau County Assessment Review Commission nassaucountyny.gov
- Nassau County Land Records Viewer (LRV) lrv.nassaucountyny.gov
- Farrell Fritz — Nassau extends 2027/28 grievance deadline to Mar 31, 2026 farrellfritz.com
Last verified October 7, 2026. Tax rules change; we re-check every page each quarter.
Educational content and estimates only, not legal, tax or financial advice. Verify with your county or town receiver, an attorney or a CPA before making financial decisions.