Since there are 193 countries in the world but only 190 member countries of the UPU, who's not part of this useful organization? There are actualy five non-member countries but two non-country members!
Country Non-Members
The five non-member countries include three former United States territories, for whom the United States Postal Service still delivers the mail - the Marshall Islands, Micronesia, and Palau. The other two are Andorra and Taiwan. Andorra is listed as a "UN member country whose situation with regard to the UPU has not yet been settled." Taiwan is an interesting case because they're not listed as being part of China, as one might expect.
Non-Country Members
The two non-country members are the 1) Netherlands Antilles and Aruba and the 2) Overseas Territories of the United Kingdom of Great Britain and Northern Ireland. The Netherlands Antilles and Aruba entered the UPU in 1875 and the Overseas Territories joined the UPU in 1877. Both are composed of territories of the Netherlands and United Kingdom, respectively. The Overseas Territories includes:
- Anguilla
- Ascension
- Bermuda
- British Indian Ocean Territory
- British Virgin Islands
- Cayman Islands
- Falkland Islands (Malvinas)
- Gibraltar
- Montserra
- Pitcairn, Henderson, Ducie and Oeno Islands
- South Georgia and the South Sandwich Islands
- St. Helena
- Tristan da Cunha
- Turks and Caicos Islands
How does one become a member of the UPU? According to their site, "any country member of the United Nations may become members of the UPU. Any country non-member of the United Nations may become member provided that its request is approved by at least two-thirds of the member countries of the UPU." Apparently, a country non-member of the U.N. doesn't even have to be a real country.
(Thanks to philatelist Kenneth S. Rothschild for the idea behind this article.)

