Mailing Standards of the United States Postal Service, International Mail Manual> 7 Treatment of Inbound Mail > 770 Undeliverable Mail > 772 Mail of Foreign Origin
At the end of the retention period (see 766), or sooner, when applicable, undeliverable items must be endorsed with the reason for nondelivery (see DMM 507).
Apply a legible postmark to the back of return letters and to the front of return postcards.
Cross out but do not obliterate the address, and draw an arrow to return address.
Undeliverable airmail letters and cards and all First-Class Mail International items marked “PRIORITY” are returned to origin by air. All parcels and other items are returned by surface. Any “AIRMAIL” or “PAR AVION” endorsements or label must be obliterated on undeliverable items returned by surface.
If the sender of a parcel has given instructions on the wrapper or dispatch note that the parcel is to be abandoned if undeliverable, endorse the parcel “ABANDONED” (see 772.32c).
Detach both copies of U.S. Customs and Border Protection (CBP) Form 3419ALT (see 713.11) and treat them in accordance with 713.33 and 713.52.
Dispatch undeliverable letters and postcards bearing a return address to the appropriate exchange office as if they were originating mail. Dispatch all other undeliverable items to the appropriate exchange office as if they were originating mail.
The following exceptions apply:
UNDELIVERABLE MAIL OFFICECANADA POST CORPORATION1860 MIDLAND AVE UNIT 1SCARBOROUGH ON M1P 2M0CANADA