ADU (Accessory Dwelling Unit) Permit in New York City (2026)
ADU (Accessory Dwelling Unit) permit requirements, fees, and process for New York City, NY. Find out if you need a permit and how to apply.
Yes, a ADU (Accessory Dwelling Unit) permit is required in New York City, NY.
A ADU (Accessory Dwelling Unit) permit is required in New York City, NY. The NYC Department of Buildings (DOB) handles permit applications for New York City. Below you will find the current thresholds, fees, and process for obtaining a adu (accessory dwelling unit) permit in New York City.
When Is a Permit Required?
When a ADU (Accessory Dwelling Unit) Permit Is Required in New York City: All ADU construction and conversions
Permit Fees
ADU (Accessory Dwelling Unit) Permit Fees in New York City: $1,000–$8,000. Estimated timeline: 3-6 months plan exam.
Estimated timeline: 3-6 months plan exam
How to Get a ADU (Accessory Dwelling Unit) Permit in New York City
Verify whether your project meets the permit threshold in New York City: All ADU construction and conversions.
Prepare your permit application and plans. Contact the NYC Department of Buildings (DOB) at https://www.nyc.gov/site/buildings/ for required documentation.
Submit your application online at https://www1.nyc.gov/site/buildings/homeowner/homeowner.page or in person at the NYC Department of Buildings (DOB).
Pay the permit fee: $1,000–$8,000.
Wait for plan check approval. Estimated timeline: 3-6 months plan exam.
Schedule required inspections through https://www.nyc.gov/site/buildings/homeowner/inspections.page. All inspections must pass before project is finalized.
Important: NYC DOB filing required. PE/RA required. Fire safety and egress requirements are strict. Basement conversions must meet ceiling height and egress window requirements.
NYC Department of Buildings (DOB)
Phone: (212) 566-5000
Website: https://www.nyc.gov/site/buildings/
Online Permits: https://www1.nyc.gov/site/buildings/homeowner/homeowner.page
Hours: Mon-Fri 8:30am-4:30pm (Borough offices vary)
Frequently Asked Questions
Can I build an ADU in New York City?
Yes, as of September 30, 2025. NYC's 'City of Yes for Housing Opportunity' zoning amendment, approved by the City Council in December 2024, allows ADUs in 1- and 2-family homes citywide. You can convert interior space (basement, attic, garage) or add a detached ADU in the rear yard. The owner must reside on the property as a primary resident. ADUs require NYC Department of Buildings permits.
What is the Airbnb law in New York City?
NYC Local Law 18 (2022), effective September 5, 2023, requires hosts to register with the city ($145/year), be present during all guest stays (no whole-home rentals when not home), and allows a maximum of 2 guests. Airbnb removed non-compliant NYC listings in September 2023. Violations carry fines from $1,000 to $7,500. This is one of the strictest short-term rental laws in the United States.
Do the ADU rules differ between NYC boroughs?
Yes. ADU applicability depends heavily on your borough and zone. Staten Island and Queens have the most single-family R1-R3 zones where detached ADUs are most applicable. Brooklyn and the Bronx have mixed zones. Manhattan has very limited single-family residential — most ADU activity there would be basement apartment conversions in brownstones. Additionally, the 152 Historic Districts add LPC review requirements that can significantly extend timelines in neighborhoods like Brooklyn Heights, Park Slope, and Harlem.
What is the City of Yes for Housing Opportunity?
City of Yes for Housing Opportunity is the largest zoning reform in NYC history, approved by the City Council in December 2024. It allows more housing types citywide including ADUs in 1- and 2-family homes, transit-oriented development near subway stations, Universal Affordability Preference (UAP) for affordable housing, and eliminates minimum parking requirements citywide. Most provisions took effect September 30, 2025.
How do I find my NYC zoning?
Use ZoLa (Zoning and Land Use Application) at zola.planning.nyc.gov — NYC DCP's official interactive zoning map. Enter your address to find zone designation, FAR limits, height limits, required yards, and special purpose districts. You can also check the NYC Zoning Resolution directly at zr.planning.nyc.gov.
Source: New York City Building Code — ADU (Accessory Dwelling Unit) Requirements. Last verified April 3, 2026. View source