GiGaBiTe
Veteran Member
Puerto Rico is a U.S. territory and thus is not international, at least according to the USPS. Airmail postage and/or customs forms are not required to send items from the mainland to Puerto Rico or vice versa.
That's not correct.
USPS said:Military Mail and some U.S. Possessions, Territories, and Freely Associated States (PTFAS) shipments also require customs documentation. This is the case even though these shipments are domestic mail or treated as domestic mail.