USPS pledges to have all Priority Flat Rate mail delivered within the 1 – 3 day time frame, regardless of what zone the mail’s destination is in. These range from a ‘zone 1’ (local) to a ‘zone 9’ (far away).

The majority of mail pieces sent through Priority Flat Rate shipping will arrive at their destination within this time frame, but some may not.įrom the starting point and ending point – where the mail is sent and where its destination is – are shipping zones. All flat rate shipping will be processed as USPS Priority Mail.ġ – 3 days is the estimated delivery date. Sizes for parcels that weigh 13 ounces or less.Flat Rate shipping typically takes one to three days to arrive at the destination – excluding Sundays or certain holidays.Contact your Business Mail Entry Unit for more information. There are special size requirements for mailing flats atĬarrier route prices. USPS Marketing Mail Carrier Route flats.'High' (the height) is the side perpendicular to the length. What is long? What is high? For flats, 'long' (the length) is the side parallel to the address as read.If so, you can save money because you'll pay the lower letter price. Is it possible to fold your flat-size piece to More about Physical Standards for Commercial Flats The higher the weight the higher the postage, especially for First-Class Mail. The maximum size for a flat provides plenty of room to put lots of material in the envelope. * Large Envelopes exceed one or more of the letter size maximum dimensions.

Be no more than 12 inches high x 15 inches long x ¾ inch thick.Have one dimension that is greater than 6-1/8 inches high OR 11-½ inches long OR ¼ inch thick.The words large envelopes and flats are used interchangeably. The Postal Service uses the word 'flats' to refer to large envelopes, newsletters, and magazines. USPS Marketing Mail Eligibility Decision Tree.Designing Letter and Reply Mail (PUB 25).

Usps flat rate box size