Unlike in some other states, Interstate Highways in New York are not directly referenced by NYSDOT with their number; instead, the letter "I" is suffixed to the number of the route on reference markers and in internal documents.

On the surface, there appears to be numerical duplication between several Interstate Highways and state routes—such as I-86 (I-86) and NY 86—but the "I" suffix that is appended to Interstate Highway numbers allows the Interstate Highway and state route to co-exist ("86I" versus "86", respectively).

I-878, located in Queens, is the shortest active route in the Interstate Highway System at 0.7 miles (1.13 km).

Small portions of I-278 in New York City are maintained by local authorities rather than the state transportation agency.

[3] In addition, parts of I-87, I-287, I-90, I-190, and I-95 are part of the New York State Thruway system and thus are maintained by the New York State Thruway Authority.