| Country | Country name |
| Colombia | conventional long form: Republic of Colombia conventional short form: Colombia local long form: Republica de Colombia local short form: Colombia |
| Comoros | conventional long form: Union of the Comoros conventional short form: Comoros local long form: Union des Comores local short form: Comores |
| Congo, Democratic Republic of the | conventional long form: Democratic Republic of the Congo conventional short form: none local long form: Republique Democratique du Congo local short form: none former: Congo Free State, Belgian Congo, Congo/Leopoldville, Congo/Kinshasa, Zaire abbreviation: DRC |
| Congo, Republic of the | conventional long form: Republic of the Congo conventional short form: Congo (Brazzaville) local long form: Republique du Congo local short form: none former: Middle Congo, Congo/Brazzaville, Congo |
| Cook Islands | conventional long form: none conventional short form: Cook Islands former: Harvey Islands |
| Coral Sea Islands | conventional long form: Coral Sea Islands Territory conventional short form: Coral Sea Islands |
| Costa Rica | conventional long form: Republic of Costa Rica conventional short form: Costa Rica local long form: Republica de Costa Rica local short form: Costa Rica |
| Cote d'Ivoire | conventional long form: Republic of Cote d'Ivoire conventional short form: Cote d'Ivoire local long form: Republique de Cote d'Ivoire local short form: Cote d'Ivoire note: pronounced coat-div-whar former: Ivory Coast |
| Croatia | conventional long form: Republic of Croatia conventional short form: Croatia local long form: Republika Hrvatska local short form: Hrvatska former: People's Republic of Croatia, Socialist Republic of Croatia |
| Cuba | conventional long form: Republic of Cuba conventional short form: Cuba local long form: Republica de Cuba local short form: Cuba |
| Cyprus | conventional long form: Republic of Cyprus conventional short form: Cyprus local long form: Kypriaki Dimokratia/Kibris Cumhuriyeti local short form: Kypros/Kibris note: the Turkish Cypriot community, which administers the northern part of the island, refers to itself as the "Turkish Republic of Northern Cyprus" (TRNC) |
| Czech Republic | conventional long form: Czech Republic conventional short form: Czech Republic local long form: Ceska Republika local short form: Cesko |
| Denmark | conventional long form: Kingdom of Denmark conventional short form: Denmark local long form: Kongeriget Danmark local short form: Danmark |
| Dhekelia | conventional long form: Dhekelia Sovereign Base Area conventional short form: Dhekelia |
| Djibouti | conventional long form: Republic of Djibouti conventional short form: Djibouti local long form: Republique de Djibouti/Jumhuriyat Jibuti local short form: Djibouti/Jibuti former: French Territory of the Afars and Issas, French Somaliland |
| Dominica | conventional long form: Commonwealth of Dominica conventional short form: Dominica |
| Dominican Republic | conventional long form: Dominican Republic conventional short form: The Dominican local long form: Republica Dominicana local short form: La Dominicana |
| Ecuador | conventional long form: Republic of Ecuador conventional short form: Ecuador local long form: Republica del Ecuador local short form: Ecuador |
| Egypt | conventional long form: Arab Republic of Egypt conventional short form: Egypt local long form: Jumhuriyat Misr al-Arabiyah local short form: Misr former: United Arab Republic (with Syria) |
| El Salvador | conventional long form: Republic of El Salvador conventional short form: El Salvador local long form: Republica de El Salvador local short form: El Salvador |
| Equatorial Guinea | conventional long form: Republic of Equatorial Guinea conventional short form: Equatorial Guinea local long form: Republica de Guinea Ecuatorial/Republique de Guinee equatoriale local short form: Guinea Ecuatorial/Guinee equatoriale former: Spanish Guinea |
| Eritrea | conventional long form: State of Eritrea conventional short form: Eritrea local long form: Hagere Ertra local short form: Ertra former: Eritrea Autonomous Region in Ethiopia |
| Estonia | conventional long form: Republic of Estonia conventional short form: Estonia local long form: Eesti Vabariik local short form: Eesti former: Estonian Soviet Socialist Republic |
| Ethiopia | conventional long form: Federal Democratic Republic of Ethiopia conventional short form: Ethiopia local long form: Ityop'iya Federalawi Demokrasiyawi Ripeblik local short form: Ityop'iya former: Abyssinia, Italian East Africa abbreviation: FDRE |
| European Union | void |