Transmittal Letter

Mailing Standards of the United States Postal Service, Domestic Mail Manual

June 23, 2019


The Mailing Standards of the United States Postal Service, Domestic Mail Manual (DMM) provides the United States Postal Service‘s official prices and standards for all domestic mailing services. Many commercial mailers find it helpful to reference these standards as they prepare and enter mailings.

For household mailers who need information about retail products and services, the Postal Service offers A Customers Guide to Mailing. New business mailers can start with Business Mail 101, which provides an overview of business mail and takes mailers through the decisions they will make when designing a mailing. Both references are updated and available on the Postal Explorer Web site at Postal Explorer also provides helpful search features, mailing tools, and price calculators to make mailing easy.

Summary of Changes

The DMM is updated frequently on Postal Explorer at Revisions are published in the Summary of Changes by effective date. Mailing standards in the DMM are revised by notices in the Postal Bulletin or the Federal Register.


The updated DMM, and prior editions, in PDF and HTML formats can be accessed on the Postal Explorer Web site at

How to Use This Book

The DMM is organized around four basic concepts - shape of mail, class of mail service, mailing method, and topic. Retail, also known as single-piece, is located at the front of the book and commercial or business mail is found in subsequent chapters. The convenient fly-out menus in the left frame provide quick access to the section needed. Quick Service Guides provide a two-page overview for specific mail classification and preparation and can be found on the Postal Explorer Web site with direct links to the DMM.


Contact your local Post Office, business mail entry office, or the Pricing and Classification Service Center (PCSC) with comments or questions about the USPS mailing standards (see DMM 608.8.4 for addresses and telephone numbers of business mail entry offices and the PCSC).

Alexander C. Petr
Product Classification