The City requires owners of buildings with three or more units to register their building annually.
Buildings with six or more units must be registered each year by April 1. Buildings with five or fewer units must be registered each year by October 1.
If you own a one or two family home but live outside of New York City, you must register your building with the City every year by October 1. If you own a one or two family home, and live in New York City, registration is not required.