Mixed franking

Usage of postage stamps from multiple polities

In philately, a mixed franking is an occurrence of postage stamps of more than one country or issuing entity on a single cover, or the occurrence of postage stamps of more than one currency of a country or issuing identity on a single cover. Since nearly all countries of the world have agreed to deliver each other's mail, it is unusual to need more than the stamps of the originating country; valid mixed frankings are uncommon and valued by collectors.

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