Postmark Calendar

Registry exchange labels resulted from the implementation of an 1882 Universal Postal Union resolution requiring that international registered mail matter bear a label or impression of a stamp with a capital letter "R" in Roman text. The United States Post Office Department opted for gummed labels which, for the most part, were produced through the joint efforts of the Government Printing Office (printing) and the Bureau of Engraving and Printing (gumming, perforating and distributing). The use of these labels by those post offices authorized to handle inbound and outbound foreign registered mail became effective Jan. 1, 1883, and stayed in effect, virtually unchanged, until Jan. 24, 1911. Such postal facilities were designated "exchange offices," and the labels have thus come to be known as "registry exchange labels" or simply "exchange labels."

During the time period these labels were in use, there were thirty-seven exchange offices that were authorized to use them. Labels are recorded from just twenty-six of these offices...