In essence, there is only one main difference between flat rate and Priority Mail: the price. All of your shipments are shipped in Flat Rate Boxes. Shipping with Flat Rate Boxes is a breeze. As long ...

revealed that its upcoming Priority Mail and Priority Mail Express flat rate stamps will feature two deep space vistas captured by the Webb observatory. Scheduled for release on Jan. 21 ...

The price of a Priority Mail flat rate envelope (size 12-1/2″ x 9-1/2″) will jump from $10.45 to $10.78 while the Priority Mail Express flat rate envelope (size 12-1/2″ x 9-1/2″) will jump ...

The U.S. Postal Service launched two new Priority Mail and Priority Mail Express stamps today at the Big Sky, Montana, Post ...