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.
The remainder of the postcode. After the initial letter(s) comes a number representing the postal district. There can be up to 100 of these in a town as 0 is used. Often, 99 (and other high numbers) is used as the postcode for PO boxes.