ISO 3166-1 alpha-3

ISO 3166-1 alpha-3 codes are three-letter country codes defined in ISO 3166-1, part of the ISO 3166 standard published by the International Organization for Standardization (ISO), to represent countries, dependent territories, and special areas of geographical interest. They allow a better visual association between the codes and the country names than the two-letter alpha-2 codes (the third set of codes is numeric and hence offers no visual association). They were first included as part of the ISO 3166 standard in its first edition in 1974.

The ISO 3166-1 alpha-3 codes are used most prominently in ISO/IEC 7501-1 for machine-readable passports, as standardized by the International Civil Aviation Organization, with a number of additional codes for special passports; some of these codes are currently reserved and not used at the present stage in ISO 3166-1.

The United Nations uses a combination of ISO 3166-1 alpha-2 and alpha-3 codes, along with codes that pre-date the creation of ISO 3166, for international vehicle registration codes, which are codes used to identify the issuing country of a vehicle registration plate; some of these codes are currently indeterminately reserved in ISO 3166-1.

The following is a complete list of the current officially assigned ISO 3166-1 alpha-3 codes, using the English short country names officially defined by the ISO 3166 Maintenance Agency (ISO 3166/MA):

User-assigned code elements are codes at the disposal of users who need to add further names of countries, territories, or other geographical entities to their in-house application of ISO 3166-1, and the ISO 3166/MA will never use these codes in the updating process of the standard. The following alpha-3 codes can be user-assigned: AAA to AAZ, QMA to QZZ, XAA to XZZ, and ZZA to ZZZ.

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