The Postal Service wants your addresses to be correct and up-to-date. We offer the following resources to help you:

Quick Service Guide 602, Addressing[1], gives an overview of addressing requirements, including diagrams for address placement.

Quick Service Guide 507, Ancillary Service Endorsements[2], describes ancillary service endorsements, the services they provide, and the associated fees. It includes a chart to help you decide which ancillary service endorsement is right for your mail.

Publication 28, Postal Addressing Standards[3], provides details for addressing requirements, including complete lists of directional's (e.g., NW, SW), suffixes, and acceptable address abbreviations.