You can report a building with no Certificate of Occupancy or an illegal one. You can also report an illegal change in the use of the Certificate of Occupancy, such as an overcrowded apartment or commercial building units being used as residential apartments. 

A Certificate of Occupancy documents the legal use or occupancy of a building. Every building built after 1938 requires a Certificate of Occupancy.

Report a problem with a building's Certificate of Occupancy.

Unauthorized Certificate of Occupancy

A Certificate of Occupancy (CO) is used to certify the legal use and occupancy of a building. The Certificate describes how a building may be occupied.

An unauthorized/improper Certificate of Occupancy can include the following:

• Not having the proper documentation for a CO
• Not having a valid CO 
• Using the building contrary to the intended purpose as described on its CO