Mineola, New York
Nassau County commercial property tax appeals
Appeals start with the Nassau County Department of Assessment and go to the Nassau County Assessment Review Commission (ARC). Here is how commercial evidence is built, filed and heard in Nassau County.
- Assessor
- Nassau County Department of Assessment
- First-level board
- Nassau County Assessment Review Commission (ARC)
- Filing deadline
- Application for correction filed with ARC from the first business day of January through March 1 (the 2027/28 window opened January 2, 2026 and was extended by the County to March 31, 2026); online through AROW or on paper
- Commercial assessment level
- Fractional level of assessment set by the Assessor for each class: 1% of market value for Class 4 commercial property on the 2027/28 roll (0.1% for Class 1 residential), with Class 2 and 4 increases other than new construction phased in over five years
- Value standard
- Market value (full value) as of the January 2 valuation date, assessed at the uniform class level required of a special assessing unit
- Valuation date
- January 2 (both the valuation date and the taxable status date)
- Assessment cycle
- Annual. The Department of Assessment publishes a new tentative roll on the first business day of January; it stays tentative for about 14 months while ARC reviews it and becomes final on April 1 of the following year
- Notices mailed
- Tentative assessments are published on the first business day of January (January 2, 2026 for the 2027/28 roll) and mailed to owners as notices of tentative assessed value
How Nassau County assesses commercial property
Nassau County is one of New York's two special assessing units, along with New York City, which means it assesses at a uniform fractional level within each of four property classes rather than at a single county-wide percentage. The Department of Assessment publishes a new tentative roll on the first business day of every January, valued as of January 2, and the roll stays tentative for about 14 months. For the 2027/28 roll the Assessor published Class 4 commercial property at a 1% level of assessment, and increases for Class 2 and Class 4 property other than new construction are phased in over five years.
The administrative appeal goes to the Assessment Review Commission, an agency independent of the Assessor. Commercial owners file Form AR2 through AROW or on paper between early January and March 1, a window the County extended to March 31 for the 2027/28 roll. ARC's rules require itemized income and expense statements for at least two years, and the Department of Assessment separately collects an annual ASIE income survey by April 1 under the Administrative Code.
ARC finishes its corrections before the final roll is filed on April 1 of the following year. Owners who still disagree commence an Article 7 certiorari proceeding in State Supreme Court within 30 days, by April 30. Because the roll is published so far ahead of the bill, a missed ARC filing is felt more than a year later, when school and general tax bills arrive on the uncorrected value.
Major commercial submarkets
- Garden City, Mineola and the Roosevelt Field retail corridor
- Lake Success and Great Neck office
- Uniondale and the Nassau Hub
- Hicksville, Bethpage and Plainview industrial
- Long Beach and South Shore multifamily
- Valley Stream and the Green Acres retail district
Uniformity authority
RPTL Article 18 (special assessing units must assess at a uniform percentage of value within each class); RPTL §720(3) (inequality proven against the class ratio)
Appeal statute
RPTL §523-b (Nassau County Assessment Review Commission application procedure); RPTL Article 7 (judicial review)
After the board
Article 7 certiorari proceeding in New York State Supreme Court, Nassau County, commenced within 30 days after the final roll is filed on April 1 (April 30, 2027 for the 2027/28 roll); Small Claims Assessment Review is limited to one-, two- and three-family owner-occupied homes
Official forms ATALI ELECTRIC fills for Nassau County
| Form | Filed with | Purpose |
|---|---|---|
| ARC Form AR2, Application for Correction (property other than a one-, two- or three-family home) | Nassau County Assessment Review Commission | The commercial grievance. States the owner's estimate of market value for the tentative roll and preserves the right to an Article 7 proceeding. |
| Income and expense statements for each year under review | Nassau County Assessment Review Commission, with the application or as ARC directs | ARC's rules call for itemized income and expenses for not less than two years, the most recent year ending five or more months before submission, with income from tenants, licensees, parking, signage and utility charges included. |
| ASIE (Assessor's Survey of Income and Expense) | Nassau County Department of Assessment, online only | Annual filing of the prior year's income and expense data for income-producing property under Nassau County Administrative Code §6-30.0, due April 1. Fully owner-occupied property files online without income data. |
Filing system: AROW (Assessment Review On the Web), ARC's online filing system for owners, commercial taxpayers and practitioners; paper applications are also accepted
Hearings and evidence
ARC reviews commercial applications on the submitted record and supporting income data, and a hearing may be requested when the application is filed. Reviews run through the 14 months the roll is tentative; ARC can reduce an assessment but never increases one, and corrections are made before the final roll is filed on April 1.
- 01Income-producing property needs itemized income and expense statements for each year under review and for not less than two years in total, and ARC can require the data before resolving a grievance.
- 02Income includes amounts paid by tenants, licensees and other users (including related entities), utility and service charges, parking and signage revenue, and certain government subsidies.
- 03Income and expense statements filed with ARC are confidential and generally not admissible in court except on the County's behalf.
- 04The annual ASIE filing with the Department of Assessment is due April 1 and must be filed online; the County has sought penalties of a percentage of market value for non-filing, which have been challenged in court.
Income evidence
Commercial property in Nassau is valued by the income approach wherever reliable income data exists, and ARC's own rules require two or more years of itemized income and expenses, so the appeal stands or falls on a clean operating history. Normalize the statements (remove debt service, depreciation and capital items, add market vacancy and reserves), capitalize at a cap rate supported by Long Island sales, and convert market value to assessed value at the published Class 4 level before comparing it to the tentative roll. Keep the ARC statements consistent with the ASIE filed with the Assessor; inconsistencies are the first thing the County checks in certiorari.
Practitioner notes
- The roll year runs well ahead of the tax bill: the 2027/28 roll published January 2, 2026 drives school bills in October 2027 and county and town bills in January 2028, so the grievance is filed about 21 months before the first affected bill.
- Class 4 increases are phased in over five years, so compare the requested value against both the full and the transitional assessment.
- Watch the County's announced deadline every year: the statutory window ends March 1, but the County extended it to March 31 for the 2027/28 roll.
- An ARC grievance is a prerequisite to Article 7. File every year to keep the certiorari path open, even for a parcel already in litigation.
Nassau County appeal questions
Last verified October 2026 against the assessor, board and statute.
Why does Nassau's assessed value look so small relative to market value?
Nassau assesses at a fractional level set for each class. On the 2027/28 roll Class 4 commercial property is at 1% of market value, so a $25 million shopping center carries a tentative assessed value of about $250,000.
When is the commercial grievance deadline?
The statutory window runs from the first business day of January through March 1. The County extended the 2027/28 window to March 31, 2026, so confirm the announced date each year before filing.
How long do I have to file an Article 7 petition in Nassau?
30 days after the final roll is filed on April 1, which makes April 30 the deadline for the 2027/28 roll. A timely ARC application is required first.
Is the ASIE the same as the ARC income statement?
No. The ASIE is an annual income and expense survey filed online with the Department of Assessment by April 1 under Administrative Code §6-30.0. ARC's application separately calls for itemized income and expenses for the years under review.
Nearby jurisdictions
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