NYC Property Tax Appeals and Assessment Appeal Services

An incorrect assessed value, tax class or exemption can affect an NYC property’s tax bill. MGNY Consulting prepares and files Tax Commission applications and represents owners through the hearing process. The Tax Commission provides an independent review of determinations made by the Department of Finance.

Discuss your property tax assessment or call (212) 343-1111 with the Notice of Property Value. The property type, claimed error and applicable filing calendar determine the approach.

The full calendar, forms and hearing process are laid out in our guide to the property tax appeal process in New York City.

What does the Tax Commission review?

Three things: the assessed value of the property, its tax class, and its exemption status. An owner who believes Finance’s assessed value or tax class is wrong can apply for correction. So can an owner whose exemption, such as J-51, 421-a, or a nonprofit exemption, is listed incorrectly, missing, or was denied, reduced or removed by Finance.

The Commission reviews the tentative assessment, which Finance publishes on or about January 15 with the Notices of Property Value, for the tax year that begins the following July 1.

When is the Tax Commission deadline?

For the 2026/27 annual assessment cycle, the received-by deadlines were 5 PM on March 2, 2026 for Tax Classes 2, 3 and 4, and 5 PM on March 16, 2026 for Tax Class 1. Those dates have passed. The ordinary statutory dates are March 1 and March 15, respectively; use the Tax Commission’s instructions for the applicable year to confirm the operative dates and any special filing route. Filing means receipt by the deadline, not a postmark.

TC600 provides a separate filing route for a Finance notice of a new or increased assessment dated after February 1: the application must be received within 20 calendar days after the notice date, with the notice attached. A revised notice reducing the assessment does not create that route. Exemption determinations and other notices should be checked against their own applicable instructions.

Which forms does the application take?

Common valuation forms include TC108 for Tax Class 1, TC101 for Class 2 or 4 properties other than condominium units, and TC109 for Class 2 or 4 condo units. TC106 covers tax classification, non-personal exemption and certain unlawful-assessment claims; personal exemptions use dedicated forms. Where TC106 is required for a combined exemption or classification and valuation claim, follow its instructions rather than filing duplicate valuation applications. The Commission’s general instructions are in Form TC600, How to Appeal a Tentative Assessment.

The required schedules depend on the property. Rental properties generally use TC201, while cooperative and condominium applicants use TC203; hotels and certain other operating properties use different schedules. TC600 provides exceptions, including residential properties with six or fewer units and no commercial space. Where both filings are required, the financial information should reconcile with the building’s RPIE filing. For 2026/27, TC309 is required with TC201 when a single parcel has a tentative actual assessed value of at least $5,400,000 and income above $100,000. The threshold applies to each tax lot in a consolidated filing, and an independent certified public accountant must sign the certification.

For 2026/27, a $175 fee applies when the assessed value on the Notice of Property Value is $2 million or more. Multiple condo units on one application are tested in aggregate. No fee is due if review is waived before the application is scheduled. The fee is billed on the property tax bill; do not send it with the application.

What happens at the hearing?

The application and supporting schedules establish the claim. Review can take place at a hearing or on the submitted papers, according to the applicable procedure. The Commission may offer a correction when the evidence supports it, such as a lower assessed value or an adjusted exemption. The records required vary by property type.

A determination that leaves the owner aggrieved is not the end of the road: further review runs to court under Article 7 of the Real Property Tax Law, through counsel, on a separate calendar.

How is this different from a DOF Request for Review?

The Tax Commission reviews assessed value, tax class and exemption claims. A DOF Request for Review asks Finance to reconsider the valuation behind its own notice. DOF provides a separate Request to Update for descriptive property information. A DOF filing does not replace a timely Tax Commission application or extend its deadline.

MGNY coordinates DOF review and Tax Commission applications where both are appropriate. The correct route depends on the issue; our DOF Request for Review and assessment corrections service explains the distinction.

The Commission has also become the forum for the newest appeal in the City: challenges to the Non-Primary Residence Surcharge, which we handle as part of our surcharge practice.

For surcharge review, Check your property in MGNY’s app for a free public DOF record lookup and available surcharge estimate. Sign in for review and document steps. The lookup is a starting point; it does not file a Tax Commission appeal.

The surcharge appeal uses Form TC107 and a separate calendar. For the 2026/27 and 2027/28 tax years, market-value challenges are due March 1, 2027 for Tax Class 2 and March 15, 2027 for Tax Class 1. An initial primary-residence challenge at the Tax Commission must also challenge market value, and DOF then defers to the Commission on residency.

If an owner applies to DOF for an exemption first, the final DOF residency determination may be appealed to the Tax Commission by the later of the applicable March deadline or 30 days from the date of that final determination. This separate residency appeal does not itself require a value challenge, and its later deadline does not extend the deadline for challenging market value. Check standing, the permitted claim and timing in the official surcharge appeal instructions. Our Form TC107 guide explains the process.

How does MGNY handle a Tax Commission appeal?

MGNY determines the appropriate application, prepares the supporting financial schedules, coordinates the required accountant’s certification where applicable, files by the relevant deadline and represents the owner at the hearing. Where there is an RPIE filing, the figures need to reconcile with the appeal’s income and expense record.

Records to gather for an assessment review

• The Notice of Property Value and any revised notice or exemption determination.
• The address, borough-block-lot, property type and current ownership details.
• Relevant income and expense records, rent roll and the property’s RPIE filing.
• Evidence supporting the claimed error, such as a recent sale, building records or exemption documents.
• Prior applications, offers or decisions for the property, if available.

Bring a revised notice promptly so its date and effect can be checked. Contact MGNY for an assessment review; the next step depends on the notice and the available filing route.

Frequently asked questions about Tax Commission appeals

How do property tax appeal services work?

MGNY reviews the Notice of Property Value, identifies the assessed value, tax class or exemption issue, prepares the appropriate application and supporting schedules, and represents the owner in the review process. A separate DOF filing may also be appropriate; it does not replace the Tax Commission application.

When is the NYC Tax Commission deadline?

For the 2026/27 annual assessment cycle, the received-by deadlines were 5 PM March 2, 2026 for Classes 2, 3 and 4 and 5 PM March 16, 2026 for Class 1. Those dates have passed. Confirm the operative dates and any special filing route in the instructions for the applicable year.

What is Form TC201?

TC201 is the Tax Commission’s income and expense schedule for rent-producing properties when that schedule is required. TC600 lists exceptions, including residential properties with six or fewer units and no commercial space. Cooperative and condominium applicants generally use TC203. Other property types may require different schedules. Where an RPIE is required, the records should reconcile across filings.

Do I need an accountant’s certification?

For 2026-27, an accountant’s certification on Form TC309 is required only for rent-producing properties filing Form TC201, where the parcel’s tentative actual assessed value is $5,400,000 or more and income exceeds $100,000. A co-op or condo board filing TC203 does not file it.

Can the Tax Commission review an exemption denial?

The Tax Commission can review qualifying DOF exemption determinations, including certain J-51, 421-a, ICIP and nonprofit exemption claims. Apply to DOF first. TC106 generally requires a relevant DOF denial, revocation or removal notice; its instructions contain a specific route for a nonprofit owner awaiting a response to a first exemption application. Personal exemptions use separate forms. Tax abatement disputes, including ICAP and co-op/condo abatements, are not reviewed on TC106.

Two explainers sit behind this service: the notice that starts the calendar and what tax certiorari is, the appeal by its legal name.

Filing locations, borough roll numbers and the deadlines that apply to each borough are on our pages for Brooklyn, the Bronx, Queens, Manhattan and Staten Island.

The assessment you are appealing comes from the Department of Finance, and the result shows up on the property tax bill; both pages explain where to look.

Official filing references: Tax Commission forms and current instructions and TC600 for the 2026/27 assessment cycle. Personal exemption and surcharge applications have separate instructions.

All Property Tax Services