Usps Flat Rate Envelope Prices 2024. Priority mail express flat rate lets you ship packages up to 70 lbs to any state at the same price. Priority mail flat rate ® products let you ship packages up to 70 lbs to any state at the same price.

Unlike some other shippers, the postal service has upfront pricing and does not add surcharges for. Postal service filed notice with the postal regulatory commission of mailing services price changes to take effect july 14,.