What you need before you start
- Your contact information — and a valid email address. ARC emails you when your application is received.
- The property — its address or parcel ID (Section, Block and Lot). Find the SBL with our Nassau tax map lookup.
- Your estimate of market value — what the property would have sold for as of the tentative roll date (January 4, 2027). Check the County’s figure in the Land Records Viewer.
- Your evidence — recent sales of similar homes nearby, your purchase price if you bought recently, an appraisal, or photos of problems. ARC’s form instructions list the documents for each property type and claim.
Which application to use
| Form | Use it for |
|---|---|
| AR1 | A one-, two- or three-family home, or an individual Class 1 condominium unit. Most homeowners use this one. |
| AR2 | Everything else: commercial property, apartment buildings, mixed-use and vacant land. See the commercial grievance guide. |
| AR3 | A dispute over your tax class or an exemption, not the value. |
Filing step by step
- Open AROW from the Assessment Review Commission’s site during the filing period. ARC also posts a step-by-step video at askarcnassau.com.
- Find your property by address or Section, Block and Lot.
- Choose the application: AR1 for a home, AR2 for other property, AR3 for a class or exemption dispute.
- Enter your estimate of market value. ARC considers the value you claim and the evidence you give to support it.
- Attach your evidence. If you can’t attach documents electronically, mail them to ARC with a cover sheet listing your application and parcel number.
- Choose how to get notices (electronic notices are an option) and submit. Watch for the email confirming ARC received your application. You can check its status in AROW at any time.
What happens after you file
ARC’s appraisers review your application; you don’t have to appear in person. ARC may offer a reduction and ask you to sign a stipulation accepting it within a set time. You don’t have to accept. ARC either lowers the assessment or leaves it unchanged; it never raises it.
- Decision: by March 31, 2028.
- If you disagree: you can seek court review, including Small Claims Assessment Review, after the final roll is published in April.
- Your bills: a reduction first shows on the October 2028 school tax bill and the January 2029 general tax bill.
Frequently asked questions
Does it cost anything to file through AROW?
No. Nassau County charges no fee to file an appeal.
Can I file on paper instead?
Yes. Mail or hand-deliver the application to the Assessment Review Commission, 240 Old Country Road, 5th Floor, Mineola, NY 11501, 9 a.m. to 4:30 p.m. Forms are on ARC’s website.
Can I file online for a commercial property?
Yes. AROW takes appeals for any type of property and any type of claim.
Do I have to go to a hearing?
No. ARC reviews the application and your evidence without an appearance.
Can I file every year?
Yes. Each year is a new filing for the next tax year.
Who can file?
The owner, or one of the owners if there is more than one. A tenant who pays all the taxes, or a contract buyer, may also qualify.
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Sources and citations
- Nassau County ARC — How to appeal your assessment nassaucountyny.gov
- Nassau County ARC — Frequently asked questions nassaucountyny.gov
- Nassau County ARC — 2028-29 calendar nassaucountyny.gov
- Nassau County Assessment Review Commission nassaucountyny.gov
- Nassau County Land Records Viewer (LRV) lrv.nassaucountyny.gov
Last verified October 19, 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.