The radiocommunication division of the International Telecommunication Union uses the following letter codes to identify its member countries. Eight countries are assigned single-letter codes (
B, 
D, 
E, 
F, 
G, 
I, 
J, 
S), while the rest have codes three letters in length.
| Code | Country |
|---|---|
| A | |
| AFG |  Afghanistan |
| AFS |  South Africa (Republic of) |
| AGL |  Angola (Republic of) |
| ALB |  Albania (Republic of) |
| ALG |  Algeria (People's Democratic Republic of) |
| AND |  Andorra (Principality of) |
| ARG |  Argentine Republic |
| ARM |  Armenia (Republic of) |
| ARS |  Saudi Arabia (Kingdom of) |
| ATG |  Antigua and Barbuda |
| AUS |  Australia |
| AUT |  Austria |
| AZE |  Azerbaijan (Republic of) |
| B | |
| B | Brazil (Federative Republic of) |
| BAH |  Bahamas (Commonwealth of the) |
| BDI |  Burundi (Republic of) |
| BEL |  Belgium |
| BEN |  Benin (Republic of) |
| BFA |  Burkina Faso |
| BGD |  Bangladesh (People's Republic of) |
| BHR |  Bahrain (Kingdom of) |
| BIH |  Bosnia and Herzegovina |
| BLR |  Belarus (Republic of) |
| BLZ |  Belize |
| BOL |  Bolivia (Plurinational State of) |
| BOT |  Botswana (Republic of) |
| BRB |  Barbados |
| BRM |  Myanmar (Union of) |
| BRU |  Brunei Darussalam |
| BTN |  Bhutan (Kingdom of) |
| BUL |  Bulgaria (Republic of) |
| C | |
| CAF |  Central African Republic |
| CAN |  Canada |
| CBG |  Cambodia (Kingdom of) |
| CHL |  Chile |
| CHN |  China (People's Republic of) |
| CLM |  Colombia (Republic of) |
| CLN |  Sri Lanka (Democratic Socialist Republic of) |
| CME |  Cameroon (Republic of) |
| COD |  Democratic Republic of the Congo |
| COG |  Congo (Republic of the) |
| COM |  Comoros (Union of the) |
| CPV |  Cabo Verde (Republic of) |
| CTI |  Côte d'Ivoire (Republic of) |
| CTR |  Costa Rica |
| CUB |  Cuba |
| CVA |  Vatican City |
| CYP |  Cyprus (Republic of) |
| CZE |  Czech Republic |
| D | |
| D | Germany (Federal Republic of) |
| DJI |  Djibouti (Republic of) |
| DMA |  Dominica (Commonwealth of) |
| DNK |  Denmark |
| DOM |  Dominican Republic |
| E | |
| E | Spain |
| EGY |  Egypt (Arab Republic of) |
| EQA |  Ecuador |
| ERI |  Eritrea |
| EST |  Estonia (Republic of) |
| ETH |  Ethiopia (Federal Democratic Republic of) |
| F | |
| F | France |
| FIN |  Finland |
| FJI |  Fiji (Republic of) |
| FSM |  Micronesia (Federated States of) |
| G | |
| G | United Kingdom of Great Britain and Northern Ireland |
| GAB |  Gabon |
| GEO |  Georgia |
| GHA |  Ghana |
| GMB |  Gambia (Republic of the) |
| GNB |  Guinea-Bissau (Republic of) |
| GNE |  Equatorial Guinea (Republic of) |
| GRC |  Greece |
| GRD |  Grenada |
| GTM |  Guatemala (Republic of) |
| GUI |  Guinea (Republic of) |
| GUY |  Guyana |
| H | |
| HND |  Honduras (Republic of) |
| HNG |  Hungary |
| HOL |  Netherlands (Kingdom of the) |
| HRV |  Croatia (Republic of) |
| HTI |  Haiti (Republic of) |
| I | |
| I | Italy |
| IND |  India (Republic of) |
| INS |  Indonesia (Republic of) |
| IRL |  Ireland |
| IRN |  Iran (Islamic Republic of) |
| IRQ |  Iraq (Republic of) |
| ISL |  Iceland |
| ISR |  Israel (State of) |
| J | |
| J | Japan |
| JMC |  Jamaica |
| JOR |  Jordan (Hashemite Kingdom of) |
| K | |
| KAZ |  Kazakhstan (Republic of) |
| KEN |  Kenya (Republic of) |
| KGZ |  Kyrgyz Republic |
| KIR |  Kiribati (Republic of) |
| KNA |  Saint Kitts and Nevis (Federation of) |
| KOR |  Korea (Republic of) |
| KRE |  Democratic People's Republic of Korea |
| KWT |  Kuwait (State of) |
| L | |
| LAO |  Lao People's Democratic Republic |
| LBN |  Lebanon |
| LBR |  Liberia (Republic of) |
| LBY |  Libya (State of) |
| LCA |  Saint Lucia |
| LIE |  Liechtenstein (Principality of) |
| LSO |  Lesotho (Kingdom of) |
| LTU |  Lithuania (Republic of) |
| LUX |  Luxembourg |
| LVA |  Latvia (Republic of) |
| M | |
| MAU |  Mauritius (Republic of) |
| MCO |  Monaco (Principality of) |
| MDA |  Moldova (Republic of) |
| MDG |  Madagascar (Republic of) |
| MEX |  Mexico |
| MHL |  Marshall Islands (Republic of the) |
| MKD |  North Macedonia (Republic of) |
| MLA |  Malaysia |
| MLD |  Maldives (Republic of) |
| MLI |  Mali (Republic of) |
| MLT |  Malta |
| MNE |  Montenegro |
| MNG |  Mongolia |
| MOZ |  Mozambique (Republic of) |
| MRC |  Morocco (Kingdom of) |
| MTN |  Mauritania (Islamic Republic of) |
| MWI |  Malawi |
| N | |
| NCG |  Nicaragua |
| NGR |  Niger (Republic of the) |
| NIG |  Nigeria (Federal Republic of) |
| NMB |  Namibia (Republic of) |
| NOR |  Norway |
| NPL |  Nepal (Federal Democratic Republic of) |
| NRU |  Nauru (Republic of) |
| NZL |  New Zealand |
| O | |
| OMA |  Oman (Sultanate of) |
| P | |
| PAK |  Pakistan (Islamic Republic of) |
| PHL |  Philippines (Republic of the) |
| PNG |  Papua New Guinea |
| PNR |  Panama (Republic of) |
| POL |  Poland (Republic of) |
| POR |  Portugal |
| PRG |  Paraguay (Republic of) |
| PRU |  Peru |
| Q | |
| QAT |  Qatar (State of) |
| R | |
| ROU |  Romania |
| RRW |  Rwanda (Republic of) |
| RUS |  Russian Federation |
| S | |
| S | Sweden |
| SDN |  Sudan (Republic of the) |
| SEN |  Senegal (Republic of) |
| SEY |  Seychelles (Republic of) |
| SLM |  Solomon Islands |
| SLV |  El Salvador (Republic of) |
| SMO |  Samoa (Independent State of) |
| SMR |  San Marino (Republic of) |
| SNG |  Singapore (Republic of) |
| SOM |  Somalia (Federal Republic of) |
| SRB |  Serbia (Republic of) |
| SRL |  Sierra Leone |
| SSD |  South Sudan (Republic of) |
| STP |  Sao Tome and Principe (Democratic Republic of) |
| SUI |  Switzerland (Confederation of) |
| SUR |  Suriname (Republic of) |
| SVK |  Slovak Republic |
| SVN |  Slovenia (Republic of) |
| SWZ |  Eswatini (Kingdom of) |
| SYR |  Syrian Arab Republic |
| T | |
| TCD |  Chad (Republic of) |
| TGO |  Togolese Republic |
| THA |  Thailand |
| TJK |  Tajikistan (Republic of) |
| TKM |  Turkmenistan |
| TLS |  Timor-Leste (Democratic Republic of) |
| TON |  Tonga (Kingdom of) |
| TRD |  Trinidad and Tobago |
| TUN |  Tunisia |
| TUR |  Türkiye (Republic of) |
| TUV |  Tuvalu |
| TZA |  Tanzania (United Republic of) |
| U | |
| UAE |  United Arab Emirates |
| UGA |  Uganda (Republic of) |
| UKR |  Ukraine |
| URG |  Uruguay (Eastern Republic of) |
| USA |  United States of America |
| UZB |  Uzbekistan (Republic of) |
| V | |
| VCT |  Saint Vincent and the Grenadines |
| VEN |  Venezuela (Bolivarian Republic of) |
| VTN |  Vietnam (Socialist Republic of) |
| VUT |  Vanuatu (Republic of) |
| W | |
| X | |
| Y | |
| YEM |  Yemen (Republic of) |
| Z | |
| ZMB |  Zambia (Republic of) |
| ZWE |  Zimbabwe (Republic of) |
The ITU also designates the following codes for other areas around the world that are not member states.
| Code | Area |
|---|---|
| A | |
| ABW |  Aruba |
| AIA |  Anguilla |
| ALS |  Alaska (State of) |
| AMS |  Saint Paul and Amsterdam Islands |
| AOE | / Western Sahara |
| ASC |  Ascension Island |
| ATA |  Antarctic |
| AZR |  Azores |
| B | |
| BER |  Bermuda |
| BIO |  Chagos Islands (Indian Ocean) |
| BLM | Saint Barthélemy (French Department of) |
| BVT | Bouvet Island |
| C | |
| CG7 | CUB(Guantanamo) (7). [6] |
| CHR |  Christmas Island (Indian Ocean) |
| CKH |  Cook Islands |
| CNR |  Canary Islands |
| CPT | Clipperton Island |
| CRO | Crozet Archipelago |
| CYM |  Cayman Islands |
| D | |
| DGA | Diego Garcia |
| E | |
| F | |
| FLK |  Falkland Islands (Malvinas) |
| FRO |  Faroe Islands |
| G | |
| GCA | United Kingdom (Non-metropolitan) – Region 1 |
| GCC | United Kingdom – Region 3 |
| GIB |  Gibraltar |
| GRL |  Greenland |
| GUF | Guiana (French Department of) |
| GUM |  Guam |
| H | |
| HKG |  Hong Kong (Special Administrative Region of China) |
| HMD | Heard and McDonald Islands |
| HWA |  Hawaii (State of) |
| HWL | Howland Island |
| I | |
| ICO |  Cocos (Keeling) Islands |
| J | |
| JAR | Jarvis Island |
| JON | Johnston Island |
| K | |
| KER | Kerguelen Islands |
| L | |
| M | |
| MAC |  Macau (Special Administrative Region of China) |
| MDR |  Madeira |
| MDW | Midway Islands |
| MRA |  Northern Mariana Islands (Commonwealth of the) |
| MRN | Marion Island |
| MRT |  Martinique (French Department of) |
| MSR |  Montserrat |
| MYT | Mayotte (Territorial Collectivity of) |
| N | |
| NCL | New Caledonia |
| NFK |  Norfolk Island |
| NIU |  Niue |
| O | |
| OCE |  French Polynesia |
| P | |
| PAQ |  Easter Island |
| PHX | Phoenix Islands |
| PLM | Palmyra Island |
| PLW |  Palau (Republic of) [7] |
| PTC |  Pitcairn Island |
| PTR |  Puerto Rico |
| Q | |
| R | |
| REU | Reunion (French Department of) |
| ROD | Rodrigues |
| S | |
| SCG | ex Serbia and Montenegro → SRB, MNE |
| SHN |  Saint Helena |
| SMA |  American Samoa |
| SPM | Saint Pierre and Miquelon (Territorial Collectivity of) |
| SWN | Swan Islands |
| SXM |  Sint Maarten (Dutch part) |
| T | |
| TCA |  Turks and Caicos Islands |
| TKL |  Tokelau |
| TRC |  Tristan da Cunha |
| U | |
| V | |
| VIR |  United States Virgin Islands |
| VRG |  British Virgin Islands |
| W | |
| WAK | Wake Island |
| WAL | Wallis and Futuna Islands |
| X | |
| XAA | shared throughout the world |
| XAX | shared by several countries, but in a restricted area of the world |
| XBR | special use |
| XBY | / Abyei area |
| XCQ | ex Caroline Islands → FSM + PLW |
| XCS | ex TCH Czechoslovakia → CZE + SVK |
| XGZ |  Gaza Strip |
| XMM | inter-ship communications |
| XOA | International Civil Aviation Organization |
| XR1 | Region 1 (RR 5.3) |
| XR2 | Region 2 (RR 5.4) |
| XR3 | Region 3 (RR 5.5) |
| XRY | Antarctic Region (RR AP 26/5.2) |
| XSC | ex SCG Serbia and Montenegro |
| XSD | ex Republic of the Sudan before 14 July 2011 → SDN + SSD |
| XSP | Spratly Islands |
| XSU | ex URS  Soviet Union → RUS + … |
| XUN |  United Nations |
| XUU | unknown site |
| XWB | West Bank |
| XWM | World Meteorological Organization |
| XYU | ex YUG  Yugoslavia → SCG… + HRV + BIH + SVN |
| XYZ | pending further developments regarding the administration responsible |
| XZZ | administrative status is subject to special arrangements |
| Y | |
| Z | |