How to Prepare for New York's Property Tax Grievance Deadlines in 2026

Own a home in New York, or planning to buy one? With the 2027 grievance cycle approaching, now is the time to put your property tax grievance deadlines on the calendar. New York carries the nation's second-highest median property tax bills, behind only New Jersey, running about 147% above the U.S. average.

With bills this high, an accurate assessment matters. If the county valued your home too high or placed it in the wrong tax class, you can file a property tax grievance. Check current New York property tax trends to see how your area compares.

Key Takeaways

• In most New York towns, Grievance Day is the fourth Tuesday in May: May 25, 2027, for the upcoming cycle.

• Nassau County files through the Assessment Review Commission (ARC) on AROW; the 2028/29 window is January 4 to March 1, 2027.

• Suffolk County's Grievance Day is the third Tuesday in May; New York City Class 1 homeowners file by March 15 with the Tax Commission.

• Outside New York City and Nassau, use Form RP-524; Nassau homeowners file Form AR-1 online through AROW.

• Filing a grievance cannot raise your assessment; under RPTL §525, the Board of Assessment Review can only reduce or confirm it.

How New York Property Taxes Are Assessed

During assessment, your local assessor estimates market value, the price your home would sell for under normal conditions. Characteristics like condition, location, and size all factor in. Assessors usually update values every year.

New York lets communities tax a percentage of that value, called the Level of Assessment (LOA). In Nassau County, the LOA for Class 1 residential properties is 0.1% (0.001). A home with a market value of $800,000 gets a tentative assessed value of $800.

Here is how a win flows to your bill: Assessed Value × Tax Rate = Annual Tax Bill. Lower the assessed value, and the bill drops proportionally.

This is how the math works in Nassau County. Your actual savings depend on your assessment and local tax rate.

Nassau County's median effective rate of 1.55% ranks among the highest in the country, so even a small reduction in assessed value returns real dollars.

If you cannot pay your New York property tax, the state charges interest that compounds daily. Meeting your grievance deadlines protects you from both an inflated bill and delinquent-tax penalties.

Understand the Property Tax Grievance Process

Filing rules differ across the state. New York City, Nassau County, Suffolk County, and upstate towns each run their own schedule, forms, and review body. Start by confirming which set of rules applies to you.

1. Key Deadlines for Grievances

Grievance Day is when the Board of Assessment Review (BAR) meets to hear complaints. In most New York towns, it falls on the fourth Tuesday in May. For the 2027 cycle, that date is May 25, 2027.

Because dates vary by county and township, contact your municipal clerk or assessor to confirm the exact date for your municipality.

Confirm specific dates with your local assessor or the ARC before filing, as some municipalities differ from the standard schedule.

You can only grieve the current tentative assessment roll. Under RPTL §524, you cannot retroactively file for past years.

Payment due dates depend on your assessed value. Without a mortgage escrow account, you pay the county directly on its due dates.

If your assessed value is under $250,000, taxes are due quarterly on July 1, October 1, January 1, and April 1. Above $250,000, bills arrive semi-annually, due July 1 and January 1.

If you pay through a bank or mortgage servicer, you won't receive a bill, but you will still receive an assessment roll. Review it; the assessed value is what you grieve.

2. Gather Documentation and Complete Your Grievance Form

Once you know your deadline, complete the correct form: Form RP-524 (Complaint on Real Property Assessment) for most of the state, or Form AR-1 for Nassau County.

The form depends on your county. Nassau County uses Form AR-1, filed through the Nassau County AROW online filing system, while Suffolk and Westchester use the RP-524.

The RP-524 is the more common form. Read every instruction; entering the wrong information can lead to denial of your grievance. The form has six sections:

1. General information: Contact information, property location and identification, name, and address.

2. Information to determine property's value: Date of purchase, purchase price, and your relation to the seller if you are not the owner.

3. Grounds for complaint: Options like unequal or excessive that show why the county's assessment is inaccurate.

4. Owner representative: Complete only if someone files the form on your behalf.

5. Signature: Sign correctly to avoid delays.

6. Stipulation to an assessment reduction: Use only if you agree to a reduced assessment with the assessor.

Focus on accuracy and clarity. Attach every supporting document you reference and keep copies of everything. If you agree to a reduced value with the assessor, get a signed copy of the stipulation.

The form is all you need to start. Once your grievance is scheduled, you will gather additional evidence to prove your case.

Escalating to the Small Claims Assessment Review (SCAR)

If you cannot reach agreement, you can request a judicial review through the Small Claims Assessment Review (SCAR). In some counties, you may receive three to four offers before this point.

SCAR is a hearing where you or your Ownwell representative present evidence before a hearing officer. There is a small fee, refunded within 90 days if you win and have already paid your taxes.

SCAR is authorized under RPTL §730 and is open only to owner-occupants of one- to three-family homes. Key details:

• The filing fee is $30, refundable if you win and have already paid your taxes.

• File within 30 days of the final assessment roll, typically around July 1.

• The hearing is informal, held before a hearing officer, not a judge.

• The hearing officer can only reduce or confirm your assessment, never raise it.

3. File the Grievance With Your Local Assessor(s)

Once the grievance form is complete, file it with the county assessor in your city or town. Ensure you get a receipt for the filing.

Some properties are assessed by both the village and the town. You must file a grievance with both entities if you are in one of those areas.

Nassau County: A Separate Grievance System

Nassau County does not follow the standard Grievance Day calendar. Instead of a town Board of Assessment Review, it uses the Assessment Review Commission (ARC).

You file online through AROW (Assessment Review on the Web) at nassaucountyny.gov. Filing is free, with no upfront cost.

For the upcoming 2028/29 tax year, the Nassau grievance filing period opens January 4, 2027, and the deadline to file is March 1, 2027. The exemption filing deadline (STAR, veterans, senior, disability) is also January 4, 2027. Missing the March 1 date means waiting a full year to challenge your assessment.

Always verify the current cycle's exact dates at ownwell.com/nassau or directly with the ARC before filing.

Nassau assesses Class 1 residential properties at a Level of Assessment (LOA) of 0.1% (0.001) of market value. A $600,000 home therefore carries an assessed value of just $600.

That math looks confusing, but the principle is simple. If your assessed value is proportionally too high relative to your home's market value, you have grounds to grieve.

Our Nassau County property tax trends put the median home value at $518,000. The median effective property tax rate is 1.55%, among the highest in the nation, and the median annual tax bill is $3,634.

If the ARC denies your grievance, you can escalate to Small Claims Assessment Review (SCAR) under RPTL §730 within 30 days of the final roll.

We file Nassau grievances through AROW at no upfront cost. Learn more about our Nassau County property tax grievance service, or read our full guide to Nassau County property taxes.

Attend Grievance Hearings and Prepare Your Case

The Board of Assessment Review (BAR) holds the grievance hearing, with three to five appointed local members. The assessor and assessor's office staff are prohibited from serving, though the assessor must attend.

You can appear in person with a representative, or submit Form RP-524 with your evidence in writing. A retained representative, like our team at Ownwell, can appear for you if you complete the owner-representative section of the form.

Filing a grievance does not increase your assessment. Under RPTL §525, the Board of Assessment Review can only reduce or confirm your current assessment. It cannot raise it above the figure already on the tentative roll.

Come prepared with strong evidence. A professional property appraisal is one of the strongest exhibits you can bring, since it reflects your home's current market value. It also accounts for condition issues like structural problems or outdated features that lower value.

Common Pitfalls To Avoid During the Grievance Process

A few habits separate successful grievances from denials:

• Fill out all paperwork clearly and concisely.

• Choose representation that can prove your case.

• Understand your documents and be ready to discuss them.

• Collect sufficient evidence to support your claim.

• Check the assessment rolls for past assessment information.

Presenting Comparative Sales Effectively

In New York, single-family homes and small multi-unit residential buildings fall into tax Class 1. That class sets the method used to assess market value, with adjustments for time of sale, location, and size.

If you use comparable sales, choose the homes most similar to yours with lower sale prices. Avoid properties that sold above market value, and keep to sales within the last year.

Another approach uses your municipality's Residential Assessment Ratio (RAR), published by the New York State Department of Taxation and Finance. Multiply your home's market value by the RAR to find an equitable assessment.

If your actual assessed value exceeds that figure, you have an unequal-assessment claim, a valid ground under RPTL §524.

The Role of a Property Tax Attorney or Tax Professional

A tax professional or property tax attorney can represent you in a grievance. If you retain representation, they attend hearings with you and prepare the documentation your case needs.

At Ownwell, our local New York experts also surface exemptions many homeowners never hear about, adding savings on top of a reduced assessment.

Exploring Local Exemptions and Incentives

Beyond grieving your assessed value, New York offers exemptions that lower your tax bill. These include benefits for seniors, veterans, and people with disabilities.

The largest is the New York School Tax Relief Program (STAR). If the home is your primary residence, you may qualify for the Basic STAR exemption or Enhanced STAR (E-STAR).

• Basic STAR: Reduces your school taxable value by $30,000 for owner-occupied primary residences with income up to $500,000.

• Enhanced STAR (E-STAR): For homeowners 65 and older with income up to $110,750 for 2026-27, it delivers a larger reduction than Basic STAR.

Applications run through the New York State Department of Taxation and Finance. See the NYS STAR resource center for eligibility and filing steps.

Filing a grievance does not affect your STAR eligibility; the two processes are independent. Explore other property tax exemptions in New York to stack additional savings.

How Ownwell Can Help

We handle the New York grievance process end to end. That means filing your Form RP-524 or Nassau AR-1 through AROW, building a comparable-sales case, and representing you before the BAR or ARC.

Our pricing is contingency-based. Our fee is 25% of your first year's tax savings, so you pay nothing if we don't reduce your bill. See Ownwell's 25% contingency pricing for the full breakdown.

What that has delivered for our Nassau County customers:

• A 93% success rate for Nassau County customers.

• $1,462 in average annual savings for our Nassau County customers.

• A 4.7-star rating across 3,000+ Google reviews.