You can visit the USPS website or contact your local post office for more information and to see the full range of flat rate packaging options available. The Priority Mail Medium Flat Rate Box and Large Flat Rate Box are up to 9+. The prices for these items may vary depending on the size and type of packaging you choose. Medium Flat Rate Boxes cost 12.35 when you purchase the postage at a USPS. It’s important to note that the USPS also offers flat rate envelopes and other flat rate packaging options. The USPS offers flat rate boxes for both domestic and international shipping, and the prices are the same for both. These prices include the cost of shipping for the box, regardless of the weight or destination. Priority Mail International Flat Rate Large Flat Rate Box, 7.15 Commercial Base 7.75 at Post Office & Online, Outside: 12 x 12 x 6 Inside: 12 x 12 x. In some cases, FedEx and UPS will cost you will over 2X the shipping cost of USPS. The USPS offers several different sizes of flat rate boxes, including a small flat rate box, a medium flat rate box, and a large flat rate box.Īs of January 2021, the prices for flat rate boxes from the USPS are as follows: If you need a large flat rate USPS Priority Mail box, make sure its. The cost of a flat rate box from the United States Postal Service (USPS) depends on the size and type of box you choose.

Large flat rate box shipping cost