NYC tax certiorari is the formal process for challenging the Department of Finance’s assessment of your property’s value, and it runs on two tracks: an administrative review at the NYC Tax Commission, followed by an optional judicial appeal in New York State Supreme Court if the administrative outcome does not satisfy you.1NYC.gov. Challenge Your Assessment Both tracks have hard deadlines, and missing either one forfeits your rights for that tax year.
Grounds You Can Challenge On
New York Real Property Tax Law Section 706 recognizes four grounds for review.2New York State Senate. New York Real Property Tax Law 706 – Grounds for Review; Contents of Petition Most owners file on the first.
- Excessive. The city’s estimated market value exceeds what the property was actually worth as of the January 5 taxable status date. Owners prove it with independent appraisals, comparable sales, or income-and-expense analysis showing the property generates less revenue than the city assumed.
- Unequal. Your property is assessed at a higher percentage of value than other properties in the same tax class, measured against the citywide ratio for that class.
- Unlawful. The assessment violates the law — for example, a qualifying exemption was not applied, or the taxing authority lacks jurisdiction over the parcel.
- Misclassification. The property sits in the wrong tax class. Because Class 1 is taxed at 19.843% and Class 4 at 10.848% for tax year 2026, a classification error can swing the bill substantially in either direction.3NYC.gov. Property Tax Rates
The RPIE Filing You Need Done First
If your property produces income and has an actual assessed value above $40,000, you must file an annual Real Property Income and Expense (RPIE) statement with the Department of Finance before you can effectively challenge the assessment.4NYC.gov. Real Property Income and Expense Filing Information The RPIE-2025 deadline is June 1, 2026, covering calendar year 2025. Owners not required to file an RPIE must instead submit a shorter claim of exclusion.
The filing covers rental apartment buildings, commercial properties with tenants, cooperatives with commercial space above 2,500 square feet, condominiums with unsold sponsor units (10% or more), hotels, parking facilities, self-storage buildings, and several other property types. Non-compliance can reach 5% of the property’s actual assessed value — a property assessed between $1 million and $5 million faces a $5,000 fine for a single missed filing, and three consecutive years of non-filing triggers the maximum penalty automatically.5NYC.gov. Real Property Income and Expense Non-Compliance Penalties More importantly for a tax challenge, non-compliance can block a Tax Commission hearing outright, and no hearing means no path to judicial review.
Filing With the Tax Commission
The Tax Commission is where every challenge begins. There is no filing fee. The application form depends on your property’s tax class:6NYC.gov. Application Forms – Tax Commission
- TC101 for Class 2 or Class 4 properties, except condominiums — most rental buildings, commercial properties, and industrial buildings.
- TC108 for all Class 1 properties, including Class 1 condominiums — one-to-three-family homes and small residential parcels.
- TC109 for condominium properties in Class 2 or Class 4.
- TC150, the income and expense schedule, attached when an income-capitalization analysis supports the claim.
Each form requires the property’s Borough, Block, and Lot (BBL) number, owner information, and operating data as of January 5. For income-producing properties, be ready to document gross income, operating expenses, and capital improvements with certified rent rolls, income tax returns, or audited financial statements.
For the 2026 assessment cycle, Class 2, 3, and 4 applications must be received by 5:00 PM on March 2, 2026. Class 1 applications must be received by 5:00 PM on March 16, 2026. Late applications are rejected outright.7NYC.gov. Forms – Tax Commission
What Happens After You File
A Commission representative is assigned to review your submission. A hearing may follow, but these are informal administrative proceedings, not courtroom trials. The owner or a representative presents the case for a reduction, and the Commission representative may ask questions about income, condition, or comparable sales.
Three outcomes are possible. The Commission may offer a settlement reducing the assessment, which resolves that tax year but waives your right to pursue the same year’s assessment in court. It may issue a final determination confirming the original value, which is the loss that opens the door to judicial review. Or it may take no action, in which case the assessment stands.1NYC.gov. Challenge Your Assessment You cannot file in court without completing this administrative step first.
Taking It to Court: The Article 7 Petition
If the administrative outcome does not satisfy you, the next step is an Article 7 proceeding in New York State Supreme Court, filed by Notice of Petition and Verified Petition with the County Clerk where the property sits. The petition names the Tax Commission and the Department of Finance as respondents.2New York State Senate. New York Real Property Tax Law 706 – Grounds for Review; Contents of Petition
Calendar the deadline now. The filing cutoff falls near the end of October of the tax year. For the 2025/26 fiscal year, petitions had to be e-filed and index numbers purchased by October 24, 2025. Miss it, and the right to judicial review for that tax year is gone. Many owners file the Article 7 petition protectively alongside the Tax Commission application, rather than waiting for the determination to arrive.
Once filed, the case moves into discovery, with both sides exchanging financial documents, appraisals, and expert reports. Most Article 7 cases settle through negotiation between the owner’s attorney and the NYC Law Department. A settlement produces a court-signed order directing the Department of Finance to adjust the assessment and issue a refund or credit. Cases that go to trial are decided by a judge on the evidence, and complex commercial matters can take several years from petition to resolution.
SCAR: The Simpler Route for Homeowners
Owners of certain owner-occupied residential property have an alternative to Article 7 called Small Claims Assessment Review (SCAR). The hearing is informal, held before a hearing officer appointed by the Chief Administrative Judge, requires no attorney, and involves no formal discovery.8New York State Unified Court System. Small Claims Assessment Review (SCAR) SCAR is available only after you have completed the Tax Commission process, and the petition must be filed within 30 days of the filing of the final assessment roll or notice of that filing, whichever comes later.9New York State Department of Taxation and Finance. Grievance Procedures For a homeowner where attorney and appraiser fees would consume most of the potential savings, SCAR is usually the practical choice.
What a Challenge Costs
Filing with the Tax Commission is free. Costs rise if the case needs professional support or moves to court.
An independent appraisal is the single most important piece of evidence in most certiorari cases. Residential appraisals for tax appeal purposes generally run from roughly $600 to $1,200. Commercial appraisals range from a few thousand dollars to well over $10,000 for large or complex properties, with additional fees if the appraiser needs to testify at trial.
Many tax certiorari attorneys work on contingency, taking a percentage of the tax savings rather than billing hourly. For NYC cases, that percentage commonly falls in the 15% to 33% range, depending on property type and complexity. Clarify in writing whether the percentage applies only to the first year of savings or extends across multiple years of reduced bills, because that one point can double or triple the effective cost of representation.
What a Reduction Actually Does
A successful challenge lowers the assessed value, which directly lowers the tax owed. If the reduction covers a year you have already paid, the Department of Finance issues a refund or credit. For mortgaged properties, the savings flow through the escrow account at the lender’s next annual escrow analysis, lowering the monthly payment. The adjustment is not immediate; it waits for the lender’s review cycle.
Article 7 cases that cover multiple tax years can produce refunds spanning several years at once. Interest on those refunds is set by city rules and may not match the cash-flow cost of carrying the overpayment in the meantime. That lag is one reason owners who challenge once often challenge every year: each year’s assessment is a separate matter with its own January status date, its own March filing, and its own October court deadline.