About Nassau County Property Tax Grievances

I recently sat down with Nassau County property tax assessment expert Mike Fuchs to discuss Nassau property assessments and how Nassau County residents can lower their tax burden.

Topics Covered:

• What are Nassau property tax assessments?
• What factors make up your property tax assessment?
• How often do property tax assessments occur?
• What is a property tax assessment grievance?
• What is the process for grieving a property tax assessment in Nassau County?
• What factors could be beneficial to your grievance and lower your assessment?
• How long does it take to submit a grievance
• How can a homeowner work with a third party for their grievance?
• What makes a good comparable?
• Does a lower tax assessment impact the resale value of your home?
• Discussing recent changes to Nassau County property taxes
• How else can a homeowner lower their property tax burden?
• What does a successful grievance mean for a homeowner?
• Mike’s top 3 takeaways for homeowners.

Nassau County Property Tax Assessments and Grievances: A Homeowner’s Guide

Property taxes are one of the largest ongoing expenses associated with owning a home on Long Island, and in Nassau County, the assessment and grievance process can be particularly confusing.

Your home’s market value, assessed value and actual property tax bill are related, but they are not the same thing. Understanding the distinction—and knowing when and how to challenge an assessment—can help homeowners determine whether they are paying their appropriate share of local property taxes.

Here is what Nassau County homeowners should know about property tax assessments, grievances and the steps they can take to potentially reduce their property tax burden.

What Are Nassau County Property Tax Assessments?

A property tax assessment is Nassau County’s determination of the taxable value assigned to a property for purposes of allocating property taxes.

It is important to understand that your assessment is not your property tax bill.

Nassau County’s Department of Assessment establishes an assessed value for properties throughout the county. Your school district, county, town and other applicable taxing jurisdictions separately establish their budgets and the amount of tax revenue they need to collect.

Your assessment effectively determines your property’s proportionate share of those taxes.

In simple terms:

Assessment = your property’s share of the tax base

Tax rates and local budgets = how much money needs to be collected

Your property tax bill = the combination of the two

This distinction is important because lowering an assessment can reduce a homeowner’s share of the tax burden, but it does not necessarily mean that the homeowner’s tax bill will decline by exactly the same percentage. Tax rates can change from year to year as school districts, municipalities and other taxing authorities change their budgets.

What Factors Make Up Your Property Tax Assessment?

For most single-family homes in Nassau County, the assessment process begins with an estimate of the property’s market value.

The Department of Assessment can consider characteristics such as:

• Location
• Lot size
• Interior living area
• Age of the home
• Architectural style
• Number of bedrooms and bathrooms
• Garage configuration
• Basement
• Property condition and improvements
• Recent construction or renovations
• Sales of comparable properties

Nassau County has historically used mass-appraisal techniques to value large numbers of properties. The county then applies a fractional Level of Assessment, or LOA, to the estimated market value to establish the assessed value.

F

or Class 1 residential properties, New York law also generally limits assessment increases to no more than 6% in one year or 20% over five years, excluding increases attributable to construction or renovations.

One of the first things a homeowner should therefore do is review the property information Nassau County has on file.

If the county believes your home is larger than it actually is, has an additional bathroom, a finished area that does not exist or another incorrect physical characteristic, that inaccurate information can affect the valuation.

How Often Do Nassau County Property Tax Assessments Occur?

Nassau County publishes a new tentative property assessment annually.

This is one of the most important aspects of the grievance process to understand: each year’s assessment is a separate determination.

Successfully grieving one year’s assessment does not permanently lock your property into that assessment indefinitely.

Nassau County’s Assessment Review Commission specifically advises homeowners to review each new assessment and file another grievance if they disagree with it—even if they are still waiting for the result of a grievance filed the previous year.

The timeline can also be confusing because there is a substantial delay between when an assessment is initially published and when taxes based upon that assessment are ultimately billed.

What Is a Property Tax Assessment Grievance?

A property tax grievance—formally an Application for Correction of Assessment—is a homeowner’s challenge to the assessment established by Nassau County.

For residential property, the most common argument is that the county’s valuation of the property is too high relative to its actual market value.

Homeowners can also challenge other issues involving classification, exemptions or calculations.

The Nassau County Assessment Review Commission, commonly called ARC, reviews these appeals.

Importantly, ARC states that it cannot increase your assessment as the result of an appeal. It can either reduce the assessment or leave it unchanged.

What Is the Process for Grieving a Nassau County Property Tax Assessment?

For a typical one-, two- or three-family residential property, the process generally begins by reviewing the tentative assessment and determining whether the market value supporting it appears reasonable.

A homeowner can then:

1. Review the property’s assessment and inventory information: confirm that Nassau County accurately describes the home and property.
2. Research comparable sales: look at recent sales of similar properties to determine whether the county’s estimated market value appears too high.
3. File an Application for Correction of Assessment with ARC: most residential homeowners use the AR1 application. Nassau County recommends filing electronically through its AROW—Assessment Review on the Web—system.
4. Provide supporting documentation when appropriate: comparable sales, photographs, appraisal information and other supporting materials can be submitted.
5. Wait for ARC’s determination: ARC may leave the assessment unchanged or offer a reduction.
6. Accept or reject a proposed settlement: if ARC proposes a reduction, the homeowner or representative may be required to accept the settlement within a specified period.

There is no Nassau County fee to file a grievance yourself, and homeowners are not required to hire an attorney or grievance company.

What Factors Could Help a Property Tax Grievance?

The central question in many residential grievances is whether the market value underlying the assessment is higher than what the property was actually worth on the applicable valuation date.

Evidence may be particularly useful when:

• Similar nearby homes sold for less than the value assigned to your property.
• The county’s records contain incorrect information about your home.
• Your home requires significant updating compared with nearby sales.
• The property has adverse characteristics that comparable properties do not.
• A recent arm’s-length sale of your home supports a lower market value.
• There are physical conditions affecting value that may not be adequately reflected in the county’s records.
• The size, condition, location or amenities of the home materially differ from properties supporting the county’s valuation.

The strongest grievance is generally based on  objective evidence of market value, rather than the argument that the homeowner simply believes the taxes are too high.

ARC does not determine whether your tax bill feels reasonable. It reviews the assessment.

What Makes a Good Comparable Sale?

Comparable sales are often the most important evidence available to owners of single-family homes.

But a comparable is not simply another house that sold in the same ZIP code.

A strong comparable should generally be as similar as possible in:

• Location
• School district
• Neighborhood
• Property type
• Architectural style
• Living area
• Lot size
• Age
• Condition
• Number of bedrooms and bathrooms
• Garage and basement configuration
• Amenities such as pools
• Overall quality and level of renovation

The timing of the sale also matters.

Nassau County recommends selecting recent sales of homes that are most similar in location, size, lot size, age and style. ARC’s own Sale Locator can make adjustments for differences among properties and changes in market conditions over time.

This is also where real estate market knowledge can become particularly useful.

Two homes may both contain 4,000 square feet on two acres, for example, but their values can be substantially different because of location, school district, condition, street, layout, architecture or quality of renovation.

Selecting comparables is ultimately a valuation exercise—not simply a search for the lowest-priced nearby sales.

How Long Does It Take to Submit a Grievance?

The application itself is relatively straightforward.

Nassau County states that the application requires only basic property information and recommends online filing because it is faster and more accurate than filing on paper.

The part that may require more time is preparing the case: checking the county’s property records, reviewing comparable sales and assembling supporting documentation.

Homeowners should therefore avoid waiting until the final day of the filing period.

There is another important distinction between filing a grievance and resolving one.

While filing can be relatively quick, ARC states that the review process itself can take up to 15 months, with final determinations generally issued by the end of March following the year in which the grievance was filed.

Can a Homeowner Use a Third Party to Grieve an Assessment?

Yes.

Homeowners can handle the process themselves or authorize an attorney, tax grievance company or other qualified representative to act on their behalf.

Nassau County requires representatives filing on behalf of property owners to register with ARC, and homeowners generally execute an authorization allowing that representative to handle the grievance.

Using a third party can make sense for homeowners who do not want to research comparable sales, monitor deadlines or handle communication with ARC themselves.

However, homeowners should understand the fee arrangement before signing an agreement.

Third-party companies may structure their fees differently, so homeowners should review:

• How the fee is calculated
• Whether a fee is due if there is no reduction
• Whether the agreement automatically renews
• Which assessment year the authorization covers
• Whether additional proceedings are included
• How tax savings are calculated

Homeowners should also avoid authorizing multiple representatives for the same assessment year. Nassau County warns that duplicate applications can result in an application being denied.

Does a Lower Property Tax Assessment Hurt the Resale Value of Your Home?

Generally, no.

A property tax assessment is not the same thing as a professional appraisal or the market value that a buyer is willing to pay for a house.

A future buyer, real estate agent or appraiser will typically evaluate the property using current market conditions and comparable sales—not simply the assessed value appearing on Nassau County’s tax roll.

In fact, from a resale perspective, a lower property tax burden can be beneficial.

Buyers typically evaluate the total cost of ownership, which includes mortgage payments, insurance and property taxes. All else being equal, a property carrying a lower annual tax burden may be more attractive than a comparable property with substantially higher taxes.

Homeowners should therefore not avoid challenging an excessive assessment because they are concerned that a lower assessment will somehow establish a lower resale price for their home.

The two valuations serve different purposes.

Recent Changes Nassau County Homeowners Should Know About

Nassau County’s assessment system has undergone significant debate and changes over the past several years, including reassessment efforts, assessment freezes and continued scrutiny regarding the equity of the system.

For homeowners, however, the practical takeaway remains the same: do not assume that last year’s assessment or grievance result automatically determines this year’s assessment.

Nassau County continues to publish annual tentative assessments, and homeowners who disagree with the new assessment need to challenge the applicable year within its filing window.

There have also been changes to property-tax relief programs.

For instance, beginning in 2026, New York State simplified the transition from Basic STAR to Enhanced STAR for qualifying seniors. Eligible homeowners receiving STAR generally no longer need to separately initiate the upgrade when they become eligible; the state can automatically determine eligibility and upgrade qualifying recipients.

In June 2026, New York also extended certain Nassau County-specific statutory provisions governing assessment and assessment review through June 30, 2028.

Because assessment rules, filing dates, exemptions and tax-relief programs can change, homeowners should verify current requirements each year rather than relying on a process they followed several years earlier.

What Else Can Nassau County Homeowners Do to Lower Their Property Tax Burden?

Grieving an excessive assessment is only one potential strategy.

Homeowners should also determine whether they qualify for any property tax exemptions.

Depending on eligibility, programs may include:

STAR

The New York State School Tax Relief program provides relief from school property taxes for qualifying primary residences.

Basic STAR and Enhanced STAR have different age and income requirements. STAR applies to school taxes rather than the entire property tax bill.

Senior Citizen Exemption

Qualifying Nassau County homeowners age 65 or older with limited income may be eligible for an additional partial property tax exemption.

Veterans Exemptions

Eligible veterans may qualify for various exemptions based on military service, combat service and service-connected disabilities.

Persons With Disabilities and Limited Income

Qualifying homeowners with disabilities and limited income may be eligible for a partial exemption.

Volunteer Firefighter and Ambulance Worker Exemptions

Eligible volunteer firefighters and ambulance workers may qualify for property tax relief.

Home Improvement Exemptions

Certain qualifying improvements may also be eligible for temporary or partial assessment relief.

Nassau County maintains a range of homeowner exemption programs, and eligibility requirements differ substantially between them.

Homeowners should review exemptions periodically—particularly after reaching age 65, becoming eligible for a veterans benefit, purchasing a primary residence or experiencing another change that could affect eligibility.

What Does a Successful Property Tax Grievance Mean for a Homeowner?

A successful grievance means ARC has agreed to reduce the property’s assessment for the applicable tax year.

That lower assessment reduces the homeowner’s proportionate share of the tax base.

It does not, however, guarantee that the homeowner’s actual property tax bill will fall by precisely the same percentage.

For example, if your assessment falls but your school district or other taxing authority increases its budget, the resulting tax rate could increase.

The more useful way to think about a grievance is: You are trying to make sure your property is carrying no more than its appropriate share of the overall tax burden.

And because Nassau County establishes assessments annually, homeowners should treat assessment review as an ongoing part of property ownership rather than a one-time event.

Top 3 Takeaways for Nassau County Homeowners

1. Review your assessment every year.

A new assessment is established annually. Check both the county’s estimated value and the physical information it has on file for your property.

2. Focus on market evidence.

A grievance is not simply an argument that your taxes are high. Comparable sales and accurate property information are among the most useful tools for demonstrating that an assessment may be excessive.

3. Understand all of your property tax relief options.

A grievance may lower your assessment, while exemptions such as STAR, senior citizen, veterans and other programs may further reduce your tax burden. Homeowners should evaluate both.

Final Thoughts on Property Tax Grievances

Nassau County property taxes can be complicated, but the fundamental concept is relatively straightforward: your assessment determines your property’s share of the taxes that must be collected within the taxing jurisdictions where you live.

If that assessment is based on a market value that appears too high, homeowners have the right to challenge it.

For homeowners considering a grievance, one of the most valuable starting points is understanding what the home was actually worth on the relevant valuation date and identifying the sales that a knowledgeable buyer, seller or appraiser would realistically consider comparable.

As a Long Island real estate professional, I regularly analyze property values and comparable sales throughout Nassau County. If you have questions about your home’s current market value or would like help understanding how your property compares with recent sales in your neighborhood, I would be happy to provide additional market context.

*This article is provided for general informational purposes only and should not be considered legal, tax or accounting advice. Property owners should consult Nassau County, New York State or a qualified tax or legal professional regarding their individual circumstances.*