US Address Format

• Traditionally, only the United States Postal Service (USPS) has been permitted to deliver to a P.O. Box.
• The Delivery Address Line and the Last Line of addresses output to the mail piece should be complete, standardized, and validated with the ZIP+4 file and City State file, respectively.
• The Postal Service defines a complete address as one that has all the address elements necessary to allow an exact match with the current Postal Service ZIP+4 and City State files to obtain the finest level of ZIP+4 and delivery point codes for the delivery address.
• Format all lines of the address with a uniform left margin. Uppercase letters are preferred on all lines of the address block.





• It is recommended that delivery address information be stored in a minimum of 30 bytes or spaces in your computer system.
• The optimum recommendation is 64 bytes or spaces to be compatible with the Postal Service National ZIP+4 database.

Delivery address line

• The Delivery Address Line, as matched against the ZIP+4 file, must be broken down into its individual components on the mailpiece with one space between address elements.
• These components are the primary address number, predirectional, street name, suffix, postdirectional, secondary address identifier, and secondary address.
• Secondary address unit designators, such as APARTMENT or SUITE, are required to be printed on the mailpiece for address locations containing secondary unit designators.

City names

• It is strongly recommended that addresses use only approved Last Line (city) names as described in the Postal Service City State file currently in effect.
• For a complete and standardized address, abbreviations for city or state names must be shown in the Postal Service City State file.
• Spell city names in their entirety. When abbreviations must be used due to labeling constraints, use only the approved 13–character abbreviations provided in the City State file.

ZIP+4

• When applying a ZIP+4 Code to a rural address, an exact match is preferred.
• If a box number is included in the address, the mailpiece must bear the appropriate ZIP+4 Code representing the range for that box number. When box number information is not available, the Rural Route base record must be used.