USPS FACTS - UNIQUE ZIP CODES

The lowest numerical zip code is 00501. It is a unique zip code for the Internal Revenue Service in Holtsville, NY.  Fisher’s Island, New York bears zip code 06390, and is the only zip code in New York, other than 00501, that does not begin with a 1. Fisher’s Island has a Connecticut zip code because the island is only accessible by ferry from Connecticut.