List of all zip codes in United States.
US Zip Code used within the United States to help the United States Postal Service (USPS) route mail more efficiently. postal codes near me are shown on the map above. The basic 5 - digit format was first introduced in 1963 and later extended to add an additional 4 digits after a dash to form a ZIP + 4 code. The additional 4 digits help USPS more precisely group mail for delivery. Though ZIP codes were originally developed for USPS, many other shipping companies such as United Parcel Service (UPS), Federal Express (FedEx), DHL, and others make use of postal codes for sorting packages and calculating the time and cost of shipping a package.