If you own a home, co-op, or condo in New York City — or rent in a building that carries one of these programs — your property tax bill may show line items that reduce your assessed tax before the final amount is calculated. Those line items are called abatements and exemptions, and they can cut thousands of dollars from what a building owner owes each year.
This guide breaks down three of the most common ones: the Cooperative and Condominium Property Tax Abatement, the J-51 Exemption and Abatement, and the 421-a Partial Tax Exemption. Whether you are a unit owner trying to understand your building’s tax structure or a building manager sorting out your annual filing, here is what each program actually does — plus the form numbers and phone numbers you need to act on it.
How Your NYC Property Tax Bill Works
The NYC Department of Finance mails property tax bills quarterly if your property’s assessed value is $250,000 or less, or semi-annually if it is above $250,000. For quarterly accounts, payments are due on July 1, October 1, January 1, and April 1. For semi-annual accounts, due dates are July 1 and January 1.
You can view your current and past bills — including any exemptions or abatements applied to your account — at the NYC Department of Finance’s online property portal at nyc.gov/nycproperty. The bill itself shows the assessed value of the property, any reductions from exemptions or abatements, the effective tax rate, and the final amount owed. Bills are generally posted and mailed about a month before the due date.
When an abatement is applied, it appears as a credit on the bill — either reducing the taxable assessed value or reducing the dollar amount owed after the rate is calculated. The difference matters because abatements and exemptions work differently under New York City Administrative Code and New York Real Property Tax Law, but both result in a lower bill.
If you have general questions about your property tax account, contact the NYC Department of Finance by calling 311 (available 24 hours a day, seven days a week) or visit nyc.gov/finance. You can also schedule an in-person appointment at a DOF Business Center or email them through the DOF contact page.
The Cooperative and Condominium Property Tax Abatement
If you own a co-op apartment or a condominium unit in New York City, your building may be receiving the Cooperative and Condominium Property Tax Abatement, which reduces property taxes on eligible units. This program is grounded in NYC Administrative Code § 11-245.3.
The abatement works at the building level, not the unit level. The co-op’s board of directors or the condo’s board of managers applies on behalf of the entire development. Individual unit owners do not file separately. The board or an authorized agent submits the application using the NYC Department of Finance’s SmartFile online portal. The annual application window runs from August 3 to February 15. Submissions after February 15 are not accepted for that tax year.
The benefit amount depends on the average assessed value of the residential units in the building:
- Average assessed value of $50,000 or less: 28.1% abatement per year
- $50,001 to $55,000: 25.2% per year
- $55,001 to $60,000: 22.5% per year
- $60,001 and above: 17.5% per year
To qualify, the development must be classified as a tax class 2 property. A building cannot simultaneously receive a J-51 exemption or a 420c, 421-a, 421-b, or 421-g benefit — though a building whose one of those benefits is expiring on June 30 of the application year can still apply for the co-op/condo abatement for the upcoming tax year.
Certain building types are not eligible at all, regardless of other criteria: Housing Development Fund Corporations (HDFC), Mitchell-Lama buildings, limited-dividend housing companies, redevelopment companies, and buildings in the Division of Alternative Management Programs (DAMP) or Urban Development Action Area Program (UDAAP).
For individual units within an otherwise-eligible development, the owner must use the unit as their primary residence, must not own more than three units in that development, and must not be receiving the clergy exemption. Units held by an LLC or a sponsor are generally not eligible, though there are limited exceptions for LLC or limited partnership ownership due to security concerns (a Cooperative/Condominium Abatement Security Waiver Application is available from DOF for those situations).
Certain larger developments must also file a prevailing wage affidavit alongside their annual application. The requirement applies if the development has 30 or more units and an average unit assessed value above $60,000, or fewer than 30 units and an average unit assessed value above $100,000. Missing this affidavit results in the entire development losing its abatement for that year, with no exception process.
To verify whether your building is currently receiving the abatement, review your property tax bill at nyc.gov/nycproperty, or contact DOF through the co-op/condo contact page. For program details, visit nyc.gov/site/finance/property/landlords-coop-condo.page, or call 311.
J-51: Tax Relief for Rehabilitated Residential Buildings
The J-51 Exemption and Abatement reduces property taxes on residential apartment buildings that undergo substantial rehabilitation or are converted from non-residential to residential use. The program is authorized under NYC Administrative Code § 11-243.
J-51 provides two connected benefits. The exemption freezes the building’s assessed value at its pre-improvement level for a period of years, so the rehabilitation work itself doesn’t immediately drive up the tax bill. The abatement provides an additional dollar credit applied against the taxes owed, calculated based on the cost of the qualifying improvements. Together, they can substantially offset the cost of upgrading older housing stock.
Qualifying work typically includes major rehabilitations of plumbing, heating, electrical systems, roofing, and building envelopes, as well as conversions of commercial or industrial buildings into multiple dwellings. The benefit period — how many years the exemption and abatement last — varies depending on the building’s location and the scope of work.
Eligibility is determined by the NYC Department of Housing Preservation and Development (HPD), not the Department of Finance. DOF administers the benefit after HPD grants approval. A property owner must first obtain a Certificate of Eligibility from HPD. Once that certificate is in hand, the owner submits the J-51 Tax Exemption and Abatement for Residential Rehabilitation or Conversion to Multiple Dwellings Application to the NYC Department of Finance.
To begin the process, visit HPD’s tax incentive page at nyc.gov/hpd – J-51. For questions about the DOF side of the process, call 311 or email through the DOF contact page for 421/J-51 matters.
To look up whether a specific building is receiving a J-51 benefit today, you can search by borough, block, and lot at nyc.gov/nycproperty. The Department of Finance also publishes downloadable J-51 benefit lookup files (PDF and Excel) for all five boroughs on its J-51 program page, organized by fiscal year.
One important note for renters: J-51 has historically had implications for rent stabilization. Buildings that received J-51 benefits were generally required to keep their apartments rent-stabilized for the duration of the benefit period. If you live in a building that received J-51 but has exited the program, and you believe your apartment was improperly deregulated during the benefit period, you may have grounds to challenge your rent with the New York State Division of Housing and Community Renewal (DHCR) or in Housing Court. This is a legal matter; consult a tenant attorney for your specific situation.
421-a: Legacy Exemptions Still Appearing on Many NYC Tax Bills
If you own or rent in a building constructed after 1971, especially in a high-demand area of the city, you may see a 421-a exemption on the property tax bill. This is a partial property tax exemption originally authorized under New York Real Property Tax Law § 421-a, designed to encourage new residential construction by temporarily reducing property taxes on newly built multifamily buildings.
The 421-a program expired for new applications in June 2022. However, buildings that qualified before the program’s expiration continue to receive their approved benefits for the full duration of their exemption periods. If you own or live in a building that received a 421-a exemption, you may still see it on your tax bill for years to come — depending on when the building was built and what benefit period was granted, this can extend well into the 2030s for some properties.
In practice, a 421-a exemption typically freezes the taxable value of the new building at the pre-construction land value, with the exemption phasing out in steps over 10, 15, 20, or 25 years, depending on the location and program terms. During the phase-out, the tax bill increases each period until the building pays full taxes at the end of the exemption. A building in the final years of its 421-a period may see notably higher tax bills as the abatement winds down.
Buildings still actively receiving 421-a benefits cannot simultaneously receive the Cooperative and Condominium Property Tax Abatement, with the narrow exception of buildings whose 421-a is expiring on June 30 of the relevant tax year, who may apply for the co-op/condo abatement to take effect for the next tax year.
For information about your building’s 421-a status, visit the DOF’s 421-a program page or look up the property at nyc.gov/nycproperty. For questions, call 311.
What to Do If an Abatement Is Missing from Your Bill
If you believe your co-op or condo building should be receiving the cooperative/condominium abatement but it doesn’t appear on your bill, start with your building’s management or board. The board or authorized agent is responsible for filing the annual application. If they missed the February 15 deadline, failed to file the prevailing wage affidavit (if required), or were denied, the abatement will not appear that year.
For J-51 issues, a missing benefit usually means the application or the HPD Certificate of Eligibility was never submitted to DOF, or the benefit period has run its course.
For 421-a, a missing benefit may mean the exemption period has expired, or that the property was never enrolled in the program at all. Check the DOF benefit lookup tools first before assuming an error.
In any case, the path forward is to contact the NYC Department of Finance directly. Call 311, visit the DOF contact page, or schedule an in-person appointment through the DOF website at nyc.gov/site/finance/property/property-tax-benefits.page. Bring your property tax bill, your property’s BBL (Borough-Block-Lot number), and any prior correspondence with DOF or HPD.
Tax advice in this article is informational. Consult a tax professional or NYC Department of Finance for your specific situation.
