The

United States Postal Service The United States Postal Service (USPS), also known as the Post Office, U.S. Mail, or Postal Service, is an Independent agencies of the United States government, independent agency of the executive branch of the Federal government of the Uni ...

uses the words "flats" and "nonletters" interchangeably to refer to large envelopes, newsletters, and magazines.

Size restrictions

To fit the definition a flat must: *Have one dimension that is greater than 6-1/8 inches high OR 11-½ inches long (the side parallel to the address as read) OR ¼ inch thick. *Be no more than 12 inches high x 15 inches long x ¾ inch thick. *Weigh no more than 13 ounces. Furthermore, the item must be somewhat bendable: see the USPS Domestic Mail Manual for exact details. This general rule does not apply to: Automation rate flats and

Standard Mail Enhanced Carrier Route flats Standard may refer to: Symbols * Colours, standards and guidons, kinds of military signs * Standard (emblem), a type of a large symbol or emblem used for identification Norms, conventions or requirements * Standard (metrology), an object th ...

Postage

The maximum size for a flat provides enough room to enclose much material. An issue, however, is that the higher the weight the higher the postage, especially for First-Class Mail.

External links and references

Domestic Mail Manual 101.2 Flats Physical Standards
United States Postal Service {{US-gov-stub