Nassau County Property Tax Grievance FAQ
Plain-English answers to common Nassau County grievance questions about ARC, AROW, deadlines, representatives, comparable sales, filing confirmation, and what happens after filing.
Reviewed by Chris Ambrosio, CPA · Updated October 7, 2026Frequently asked questions
These are the questions homeowners repeatedly run into when they first encounter Nassau County’s assessment system. The answers below are intentionally short; the linked GrieveItNow guides go deeper on each topic.
What am I actually appealing?
You are appealing the property assessment. ARC reviews the assessment; it does not set the tax rates charged by school districts, towns, or other taxing jurisdictions.
Do I need an attorney?
No. Nassau County says you are not required to use an attorney, and homeowners may file their own appeals.
What is AROW?
AROW is Assessment Review on the Web, Nassau County ARC’s online system for property assessment appeals, status tracking, public inquiry, and residential sales research.
When can I file for the 2028/29 assessment?
Nassau County currently lists January 4, 2027 through March 1, 2027 as the filing period for the 2028/29 assessment.
Do I have to use comparable sales?
The County says the AROW Sales Locator is optional. Comparable sales can still be useful evidence when evaluating residential market value.
What happens after I file online?
A successful online transmission generates an appeal number. Keep the confirmation and monitor AROW or your selected correspondence method for ARC notices and the eventual determination.
Can GrieveItNow file if I do not know my Parcel ID?
Yes. Parcel ID is optional at signup. GrieveItNow locates and verifies the parcel before the representative authorization is completed.
How much does GrieveItNow charge?
GrieveItNow charges a flat $99 fee for Nassau County research, preparation, and filing and does not take a percentage of the homeowner’s savings.
Official filing dates and procedural references are based on current Nassau County Assessment Review Commission and Department of Assessment materials. County notices and rules control if they change. Educational information is not a guarantee of a reduction.
Reviewed by Chris Ambrosio, CPA
A Certified Public Accountant with over 13 years of financial experience. Chris spent more than six years at a Big Four accounting firm auditing financial services companies, followed by a year in private equity before nearly six years in the real estate industry as a Senior Manager of Accounting. He brings institutional-grade financial analysis to every property tax grievance filing.