Where is an official code for the European Union defined?

Question

There is no code for the European Union in ISO 3166 or UN.M49. CLDR states that its own list does not contain a code for the European Union. I've seen the code "EU" used, but I can't find any official list that contains it. Is it in any official list of codes?

Answer 1

As it turns out, it is not in a list per se, but the code EU was officially "reserved" by the ISO 3166 Maintenance Agency to represent the European Union. This is discussed in an old version of the Maintenance Agency FAQ:

You can use EU for the name European Union. Please note that this is not an official ISO 3166-1 country code. The European Union is not a country but rather an organization. As such it is not eligible to be formally included in ISO 3166-1. Recognizing, however, that many users of ISO 3166-1 have a practical need to encode that name the ISO 3166/MA reserved the two-letter combination EU for the purpose of identifying the European Union within the framework of ISO 3166-1.

This document is apparently no longer available, although parts of the statement are widely quoted on other Web sites (e.g. on Wikipedia).