Long Island property tax grievance — complete guide

Long Island property taxes are among the highest in the United States — median bills of $11,000-$12,000/yr across both counties. Filing a grievance is the single most effective way to lower yours, and it’s essentially risk-free: Boards of Assessment Review (and Nassau’s ARC) cannot raise your assessment in response to a complaint. The worst case is no change.

Successful grievances typically reduce assessed value 5–15%. On a median LI home that translates to $550-$1,700/yr in ongoing savings, every year, until the next reassessment puts you back up.

Not sure if you have a case? Take our 2-minute Should I Grieve quiz — it walks through the rule-of-thumb signals (purchase price below assessment, recent comparable sales, no recent reassessment) and tells you whether filing is worth your time.

You can also sign up for free grievance-window alerts for your parcel — one email per quarter when the grievance window opens or your assessment changes, so you never miss the deadline.

Nassau’s Assessment Review Commission handles grievances for every Nassau homeowner, regardless of which town you’re in. Use the town pages below for town-specific tax data; file your grievance through ARC.

Each Suffolk town runs its own Board of Assessment Review. You file with the BAR for the town your property is in.