Mailing Standards of the United States Postal Service, International Mail Manual> 2 Conditions for Mailing > 240 First-Class Mail International > 245 Mail Entry and Deposit
First-Class Mail International items bearing a computer-generated customs form with customs data that has been electronically transmitted (e.g., using Click-N-Ship service, an authorized PC Postage vendor, or the USPS Web Tools system) may be deposited through any of the following methods, provided postage is paid by a means other than the use of postage stamps:
Note: First-Class Mail International letter-size and flat-size items weighing 13 ounces or less and bearing only postage stamps may also be deposited through the aforementioned methods, if the item does not require a customs form.
Customers must present the following First-Class Mail International items requiring a customs form to an employee at a Post Office retail service counter. Deposit and pickup methods listed in 245.11 are prohibited. The Postal Service will return improperly presented items to the sender for proper entry and acceptance.
Mailers who enter volume mailings paid with a permit imprint under 243.3 must enter such items through a business mail entry unit (BMEU) or, when authorized by the district BMEU manager, through a detached mail unit (DMU) at a mailer’s plant.