One of the advantages for employees in a group health plan is the contribution most employers make toward the cost of the health coverage premium â in many cases, employers pay one-half or more of the monthly premium for an employee.
The basic format consists of five decimal numerical digits. An extended ZIP+4 code, introduced in 1983, includes the five digits of the ZIP code, a hyphen, and four additional digits that determine a more specific location within a given ZIP code. The USPS provides a free online lookup tool for ZIP codes.
An extended ZIP + 4 code includes the five digits of the ZIP code, a hyphen and then four more digits, which allow a piece of mail to be directed to a more precise location than by the ZIP code alone. ZIP Code was originally registered as a trademark by the U.S. Postal Service but its registration has since expired.