Publication 28, Postal Addressing Standards, provides guidance on the most efficient means to output an address to a mailpiece. It is necessary to use address validation tools when entering addresses into the data, and then to use list maintenance or list management to ensure that the content of the address is accurate and complete. A number and variety of address information products and services are available to assist in validation of addresses on entry and list maintenance. The standards facilitate the use of these products by providing a uniform file format for data entry of address information, as well as for extraction of information for matching purposes.
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.
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. A complete address may be required on mail at some automation rates. Refer to the Mailing Standards of the United States Postal Service, Domestic Mail Manual (DMM®) for more detailed information.
A standardized address is one that includes all required address elements and that uses the Postal Service standard abbreviations (as shown in this publication or in the current Postal Service ZIP+4 file).