NYC Certificate of Occupancy FAQ

A Certificate of Occupancy (C of O) is a document issued by DOB certifying that a building complies with the Building Code and is approved for a specific use and occupancy. It specifies the permitted use (residential, commercial, etc.), number of dwelling units, and maximum occupancy.

Final C of O: permanent certificate for completed buildings. Temporary C of O (TCO): allows occupancy while minor work is completed (must be renewed every 90 days). Letter of No Objection: for pre-1938 buildings that may never have received a formal C of O.

Enter any NYC address into RegWatch to see the Certificate of Occupancy status, including type (final, temporary, or none), permitted use, and dwelling unit count. This is cross-referenced with actual building conditions and violations.

Buildings constructed before 1938 may not have a C of O. DOB can issue a Letter of No Objection based on the Multiple Dwelling Registration. However, buildings constructed after 1938 without a C of O may be technically uninhabitable and may face DOB violations.

An illegal conversion is the alteration of a building to create additional dwelling units or change the use without DOB approval and an updated C of O. Common examples include converting basements/cellars to apartments, splitting apartments, or using commercial space as residential. Illegal conversions carry serious penalties.

Illegal conversions can delay or kill deals. Banks may decline financing, title companies may raise objections, and buyers face liability for correcting the conversion. Insurance may not cover incidents in illegally converted spaces. DOB violations for illegal conversions carry fines up to $25,000.

A TCO allows occupancy while minor work remains incomplete. TCOs expire every 90 days and must be renewed. A building with an expired TCO and no final C of O has unresolved compliance issues. Developers must track TCO renewals carefully.

Yes. The C of O is amended through an Alteration Type 1 (A1) application when the building use, egress, or occupancy changes. The new C of O replaces the previous one. Minor changes may only require an A2 or A3 permit without changing the C of O.

A Letter of No Objection (LNO) is issued by DOB for pre-1938 buildings where DOB has no objection to the current use. It functions similarly to a C of O for these older buildings that may predate the C of O requirement.

The C of O must be consistent with the property's zoning. A building cannot receive a C of O for a use not permitted by zoning (e.g., commercial use in a purely residential zone). Zoning changes can create non-conforming uses where the C of O permits a use that new zoning would not allow.

Operating without or in violation of the C of O can result in DOB violations with fines up to $25,000, vacate orders requiring building evacuation, and ECB judgment liens for unpaid fines. Banks may refuse to finance properties with C of O discrepancies.

Yes. RegWatch includes Certificate of Occupancy status, type, permitted use, and dwelling unit count in every property profile. This is cross-referenced with actual building conditions, violations, and zoning to identify potential discrepancies.