The USPS Domestic Mail Manual is a comprehensive guide that outlines all the rules, standards, and procedures for mailing within the United States. The current version of the DMM is available online at the USPS website.

 
To view the USPS Domestic Mail Manual (DMM): Click Here

Note: The DMM defines Mailing Standards, what is acceptable to mail and how it should be prepared. It provides guidelines for bundling and packaging to comply with USPS safety standards and more.