1. The Issuing Agency Determines the Available Review Process
A larger bill does not necessarily mean an incorrect assessment. Identify whether the issue involves value, exemptions, unpaid taxes, or a separate tax determination.
Property Assessments and Tax Bills Involve Different Decisions
An assessment establishes taxable value, while the bill also reflects tax rates and exemptions. A grievance cannot ordinarily challenge an adopted rate. Overdue bills and liens require a separate review of local tax obligations.
The Notice Shows Where to Respond
Check the parcel number, roll year, agency, and grounds for review. A tentative assessment requires a different response from a state deficiency notice or IRS examination letter. Keep the full notice and mailing date.
2. Nassau Assessment Appeals Begin with the County Commission
Nassau County's Assessment Review Commission (ARC) reviews challenges to county property assessments under Real Property Tax Law § 523-b. Owners file an Application for Correction of Assessment, not a town grievance.
Filing Dates and Forms Depend on the Assessment Year
For the 2028–2029 tax year, ARC accepts applications from January 4 through March 1, 2027. This concerns the 2027 tentative roll, not that year's tax bill. File through Assessment Review on the Web (AROW), by mail, or in person.
Use AR1 for qualifying one- to three-family homes and Class 1 condominium units, AR2 for other property types, and AR3 for classification or exemption disputes. Keep filing confirmation. An attorney is optional, and ARC charges no application fee.
Assessment Evidence Must Fit the Valuation Date
Use comparable sales reflecting condition, size, location, and the valuation date. Photographs, appraisals, or corrected measurements can support a reduction. Income-producing properties may require operating statements and rent rolls.
An AR3 exemption appeal has an additional restriction: ARC reviews a prior Department of Assessment exemption determination using the record already submitted to that department. New exemption documents generally cannot be introduced at ARC. This differs from broader property tax assessment disputes.
3. Suffolk Assessment Grievances Start with the Town
Suffolk County taxpayers generally challenge a town assessment through the local assessor and Board of Assessment Review (BAR). Each town sets the initial filing instructions and hearing arrangements.
Grievance Day Sets the Administrative Deadline
Suffolk town boards generally hold Grievance Day on the third Tuesday in May, unlike the statewide fourth-Tuesday default. Real Property Tax Law § 524 allows filing with the assessor before the hearing or with the BAR at the hearing. Confirm town instructions and any separate village assessment.
Form RP-524 identifies the assessment, requested correction, and grounds: excessive, unequal, unlawful, or misclassified. Keep proof of filing; informal discussion does not preserve appeal rights.
Good Comparisons Explain the Requested Reduction
Use comparable sales within the assessing unit, adjusting for condition, improvements, lot size, and use. Consider the assessment ratio when assessed values differ from market values. Save the roll, exhibits, and BAR decision.
4. Court Review Follows the Administrative Challenge

Article 7 permits judicial review after an administrative grievance. Small Claims Assessment Review (SCAR) and ordinary proceedings have different eligibility, deadlines, and service rules.
SCAR Is Limited to Qualifying Properties
Under § 730, SCAR generally covers eligible owner-occupied one-, two-, or three-family residential property and certain narrowly defined unimproved parcels. Certain Class 1 or homestead condominiums qualify; commercial property does not. Equalized value generally cannot exceed $450,000 unless the reduction requested is no more than 25% of assessed value.
A prior grievance is required, and the petition cannot seek a lower assessment than the original grievance requested. SCAR generally requires a Supreme Court petition within 30 days after the final roll and a $30 fee. Nassau lists May 1, 2028, for the 2028–2029 roll, subject to later-decision exceptions. Section 730(8) requires sending copies to specified officials within ten days after filing.
Ordinary Article 7 Proceedings Have Separate Requirements
Other owners may use ordinary Article 7 proceedings. Sections 702 and 706 establish the usual 30-day filing period after the final roll and permitted grounds. Nassau has additional rules under § 523-b.
The petition must identify a timely prior grievance. A stipulated assessment entered on the final roll can bar further review. Check court filing and service rules.
5. State and Federal Tax Notices Use Different Procedures
Property appeals do not resolve income tax audits, sales tax liabilities, or IRS adjustments. Distinguish preliminary audit proposals from notices granting formal protest rights.
Sales Tax Duties Depend on Location and Transaction Type
New York State administers sales and use taxes together with local taxes. Suffolk County's general combined rate became 8.75% on March 1, 2025, although special rates and transitional exceptions apply. Businesses must check transaction dates, taxability, exemptions, and delivery locations.
Retain invoices, sales reports, exemption certificates, and previously filed returns. Cross-border transactions raise state and local tax questions beyond this county-focused assessment guide.
Audit Notices Require a Separate Deadline Check
For qualifying state notices, request a conciliation conference or petition the Division of Tax Appeals. A 90-day deadline commonly applies to Notices of Deficiency or Determination, but consult the notice. Proposed Audit Changes alone do not grant those rights.
IRS examinations follow separate federal procedures, not ARC, BAR, or state Tax Appeals rules. Preserve returns, correspondence, and supporting records. Broader tax audit and adjustment procedures should be reviewed separately from property assessment relief.
21 Oct, 2026

