A code for a specific recipient
Some ZIP Codes are assigned to a particular organization or high-volume mail recipient rather than a broad neighborhood delivery area. These are commonly called unique ZIP Codes.
Why organizations use them
A dedicated code can help route large quantities of mail efficiently to a major company, government agency, university or other institution. It can also simplify internal mail handling.
Not a general neighborhood code
A unique ZIP Code should not be assumed to represent all nearby homes or businesses. Its use may be limited to the designated recipient or a specific postal arrangement.
How to confirm one
Use the exact recipient address and official postal lookup tools. A directory record can be informative, but the current mailing instructions from the organization and USPS should take priority.