ISO 3166-1 alpha-3 is used in ISO/IEC 7501-1 for machine-readable passports.

For current codes see: 3166-1

Reserved Code Elements list

The following alpha-3 codes are user-assigned: AAA, QMA-QZZ, XAA-XZZ, and ZZZ.

The following alpha-3 codes are subject to a transitional reservation:

• BUR - Burma, now Myanmar
• BYS - Byelorussian SSR, now Belarus
• CSK - Czechoslovakia, now Czech Republic and Slovakia
• NTZ - Saudi-Iraqi neutral zone
• ZAR - Zaire

The following three letter codes are subject to an indeterminate reservation, having been notified to the United Nations Secretary-General under the 1949 and/or 1968 Road Transport Conventions:

• ADN - Aden
• BDS - Barbados
• BRU - Brunei
• CDN - Canada
• EAK - Kenya
• EAT - Tanganyika
• EAU - Uganda
• EAZ - Zanzibar
• GBA - Alderney
• GBG - Guernsey
• GBJ - Jersey
• GBM - Isle of Man
• GBZ - Gibraltar
• GCA - Guatemala
• HKJ - Jordan
• MAL - Malaysia
• RCA - Central African Republic
• RCB - People's Republic of Congo
• RCH - Chile
• RMM - Mali
• RNR - Zambia
• ROK - South Korea
• ROU - Uruguay
• RSR - Southern Rhodesia
• RSM - San Marino
• SLO - Slovenia
• SME - Suriname
• TMN - Turkmenistan
• WAG - Gambia
• WAL - Sierra Leone
• ZRE - Zaire

The following alpha-3 code elements are subject to an exceptional reservation:

• ASC - Ascension Island - reserved for UPU, also used by ITU
• CPT - Clipperton Island - reserved for ITU
• DGA - Diego Garcia - reserved for ITU
• FXX - Metropolitan France - reserved on behalf of France
• GGY - Guernsey - reserved for UPU
• IMN - Isle of Man - reserved for UPU
• JEY - Jersey - reserved for UPU
• TAA - Tristan da Cunha - reserved for UPU

For the time being, ISO 3166 MA has agreed not to use the following codes, taken from ISO/IEC 7501-1 (Machine readable travel documents), as alpha-3 country codes:

• GBD - British Dependent Territories Citizen
• GBN - British National (Overseas)
• GBO - British Overseas Citizen
• GBP - British Protected Person
• GBS - British Subject
• UNO - United Nations Official
• UNA - United Nations Specialized Agency Official
• UNK - Kosovo resident, issued travel document by UNMIK