Mixed franking

In philately, a mixed franking is an occurrence of postage stamps of more than one country or issuing entity on a single cover,[1] or the occurrence of postage stamps of more than one currency of a country or issuing identity on a single cover.

Since this only happened during the first few decades of stamp usage, and only for the few letters that were sent great distances, very few covers have survived.

Another form of mixed franking occurs in transitional periods, such as after the Irish Free State's establishment from the United Kingdom in 1922 and 1923.

An example of involuntary mixed franking is when Germany took over Austria in the Anschluss in 1938; during the several months while Austrian stamps were still accepted, Austrians sending mail to Germany were required to include a German stamp on the envelope.

Sometimes illegitimate mixed frankings occur when a postal user adds another country's stamps to an envelope just for fun.

Registered cover with mixed franking of two issuing entities. 5 kopecks Soviet stationery, 5 kopecks Soviet postage stamp and 10 kopecks Latvian postage stamp, postmarked 27 November 1991, just a few months after the recognition of Latvian independence by the Soviet Union.