Nassau County tax rolls are out. Here's how to grieve your assessment

January marks the release of Nassau County’s tax rolls, prompting hundreds of thousands of homeowners to begin the process of contesting the county’s assessed value of their properties in hopes of lowering their tax bill.

Nassau residents pay some of the highest taxes in the country. It is one of 13 counties in the United States where the median annual property tax bill was higher than $10,000 as of 2021. Fighting for tax reductions has become the norm.

County officials determine property taxes by assessing the value of homes using what critics call an outdated calculation that doesn’t reflect the current real estate market. That forces homeowners to file a so-called "grievance," disputing the county’s assessment of their property and telling officials what they think their home is actually worth.

Here is the process to lower a homeowner’s tax bill.

How are my property taxes calculated?

Your property taxes are calculated by the county. Officials use property values set under former Nassau County Executive Laura Curran, who spent more than $5 million in 2018 on a countywide program to assess the values used to calculate taxes for about 425,000 properties. The county multiplies the value of a home by a so-called "level of assessment," or a rate of 0.1%. This means for a residential property worth $1 million, the county says its assessed value is $1,000.

The county’s assessment of property values, and its assessment rate of 0.1%, have been frozen for years — leaving many homeowners frustrated with how the county calculates their taxes. They can appeal the county’s assessment of their home through a grievance.

If you file a grievance, your property is not assessed using the Department of Assessment’s rate of 0.1%, but by the county’s Assessment Review Commission (ARC) instead. Last year, the ARC rate was 0.06%.

ARC sets its rate by comparing recent home sales in the area to their assessed values. It’s unclear what the ARC rate will be for the 2026-2027 tax season. If it remains 0.066%, that means the same $1 million home would be assessed at $660.

Officials then apply county, municipal and school district tax rates, based on where you live, to the assessed value of your home. For example, the Nassau County property tax rate in 2021 was 5.2 per $1,000 of a home’s full market value, plus municipal tax rates for towns and/or villages, school district taxes and taxes for special districts.

In 2021, residents paid up to 18.1 per $1,000 in municipal taxes, depending on the town and village, and up to 42.6 per $1,000 in school district taxes.

Why were my taxes calculated this way?

The answer is complex and involves many factors, like aging policies, the politics behind the tax system and even the software program the county used to reassess people’s homes under Curran.

"The system is irrevocably broken. It has not been maintained, it has not been updated, and the only chance people have to be fairly assessed is to file a grievance of their assessment every year ... If people don’t file successful grievances, they will pay higher tax rates," attorney Jeff Gold, an expert on Nassau’s tax system, told Newsday.

Gold, who files grievances on behalf of homeowners part-time, served on the county’s Board of Assessors in the early 2000s. He then became the ARC commissioner from 2005 to 2008. In 2017, Gold ran for the county legislature on a platform of reforming the county’s tax assessment system.

People who don't file a grievance are paying for those who do, Gold said

The tax firms representing homeowners who challenge the county’s tax system have long-standing political ties, which critics say helps keep the system unchanged. Such firms collected $506.5 million in client fees between 2012 and 2019, Newsday previously reported. A political-action committee backed by the companies gave $256,725 to Republican campaign committees, candidates and elected officials in Nassau County from January through August of 2022. The PAC gave $15,000 to Democratic Gov. Kathy Hochul’s campaign over the same period.

How can I file a tax grievance?

Homeowners who want to challenge the county’s assessment must go through the Nassau County Assessment Review Commission. You have two options: hire a lawyer who will take a cut of what you save on taxes, or do it yourself.

If you want to personally file a grievance, start by making an account on the ARC website. For help with the process, you can watch this video or attend a grievance workshop at your local library listed here.

After registering, select "File an appeal" on the left side of the page. Choose the type of property you’re looking to appeal (there are four different class types in Nassau County) and fill out the six-part tax grievance application. The application will prompt you to enter how much you think your property is worth. Experts recommend using the county’s Land Records Viewer tool or a website like Zillow to find recently sold homes in your neighborhood that are similar in size, but sold in the last year or so at a price lower than your assessed value. Average the sales prices of a few of those homes, and use that number as your estimate.

The application will ask you to note how many kitchens, bathrooms and bedrooms are in your home. You’ll also be prompted to enter details about air conditioning, swimming pools, nearby golf courses and other information.

In the fifth section, enter the addresses and dates of sales for those recently sold homes you found in your neighborhood. This serves as evidence for the county that your home is being unfairly assessed. Finally, submit your application.

If you do not want to file a grievance on your own, you can hire a tax firm to file one on your behalf. Those companies tend to charge you between 30% and 50% of what you save on your taxes.

I filed a grievance. Now what?

Eight to 15 months after you file a grievance, you will get a letter from the ARC. If you’re unhappy with your new assessment, you can ask for a second review. This can take another month or two.

Eventually, you will get a final assessment from the ARC by mail. If you’re unhappy with the result, you can request a judicial review process called a Small Claims Assessment Review (SCAR) through the county clerk’s office. You will have a court hearing where you can present evidence of properties that have sold recently in your neighborhood to support your claim. Filing this petition costs $30, but you may be reimbursed by the county if you win your case.

By April 1, 2026 the county will publish its final assessments — for homeowners who grieved and those who did not — and determine how much money they need for school, general and county taxes. Any assessment you get during the 2026-2027 grievance period will reflect how much you pay in school taxes in 2026 and county taxes in 2027, according to Gold.

Filing a successful grievance has proved to lower your taxes: Nearly 70% of property owners successfully filed a grievance in 2023-24, reducing their property taxes by an average of 6.4%. But critics of the system say the grievance process creates a two-tier system that disadvantages many homeowners. A Newsday investigation found $1.7 billion in taxes between 2010 and 2017 was punted from homeowners who appealed their assessments to those who did not. More than 60% of homeowners appealed their assessments, the investigation found. Their typical tax bill went up 5%, while the remainder of homeowners — 40% — saw their tax bill spike 36%.

Aren’t there other exemptions I can file to lower my bill?

U.S. veterans who were honorably discharged may qualify for up to 15% to 25% tax reduction. Their surviving spouses who have not remarried, dependent parents and dependent children may also qualify.

Those 65 or older with an annual household income of $98,700 or less (that number may change this year) may qualify for the Enhanced School Tax Assessment Relief program and the Senior Citizens Property Tax Exemption.

Anyone who has been a volunteer firefighter or ambulance worker for at least five years may qualify for a Real Property Tax Exemption.

Those with a disability and a capped income may qualify for a significant tax reduction.

Can I postpone my taxes?

No. Either you file during the grievance period or you lose your opportunity to challenge your property assessment.

 What are some key dates I should be paying attention to?

• Jan. 21: Deadline to challenge property assessments for residents in the City of Long Beach.
• Feb. 18: Deadline to challenge property assessments for most villages in Nassau County.
• March 3: Deadline to appeal the county’s assessed value of your property. It’s possible county Executive Bruce Blakeman will extend this deadline, as county executives have done for the past eight years.
• April 30: Deadline to petition the Assessment Review Commission’s decision on your property in most villages in Nassau County.
• April 30: Deadline to petition the Assessment Review Commission’s decision on your property in the city of Long Beach.
• June 17: Deadline to challenge property assessments for the City of Glen Cove.
• Aug. 31: Deadline to petition the Assessment Review Commission’s decision on your property in the City of Glen Cove.
• Nov. 18: Deadline to challenge property assessments for the villages of Freeport, Great Neck Plaza, Kensington, Russell Gardens, Saddle Rock and Thomaston.
• Jan. 31, 2026: Deadline to petition the Assessment Review Commission’s decision on your property in the villages of Freeport, Great Neck Plaza, Kensington, Russell Gardens, Saddle Rock and Thomaston.
• April 1, 2026: ARC publishes final 2025-2026 assessments.
• April 30, 2026: Deadline to request a judicial review or SCAR.
• Oct. 1, 2026: Town receiver mails your school tax bill.
• Jan. 1, 2027: Town or city receiver mails your general tax bill.