| Country | Country name |
| Guinea-Bissau | conventional long form: Republic of Guinea-Bissau conventional short form: Guinea-Bissau local long form: Republica da Guine-Bissau local short form: Guine-Bissau former: Portuguese Guinea |
| Guyana | conventional long form: Cooperative Republic of Guyana conventional short form: Guyana former: British Guiana |
| Haiti | conventional long form: Republic of Haiti conventional short form: Haiti local long form: Republique d'Haiti/Repiblik d' Ayiti local short form: Haiti/Ayiti |
| Heard Island and McDonald Islands | conventional long form: Territory of Heard Island and McDonald Islands conventional short form: Heard Island and McDonald Islands abbreviation: HIMI |
| Holy See (Vatican City) | conventional long form: The Holy See (State of the Vatican City) conventional short form: Holy See (Vatican City) local long form: Santa Sede (Stato della Citta del Vaticano) local short form: Santa Sede (Citta del Vaticano) |
| Honduras | conventional long form: Republic of Honduras conventional short form: Honduras local long form: Republica de Honduras local short form: Honduras |
| Hong Kong | conventional long form: Hong Kong Special Administrative Region conventional short form: Hong Kong official long form: Xianggang Tebie Xingzhengqu official short form: Xianggang abbreviation: HK |
| Hungary | conventional long form: none conventional short form: Hungary local long form: none local short form: Magyarorszag |
| Iceland | conventional long form: Republic of Iceland conventional short form: Iceland local long form: Lydveldid Island local short form: Island |
| India | conventional long form: Republic of India conventional short form: India local long form: Republic of India/Bharatiya Ganarajya local short form: India/Bharat |
| Indian Ocean | void |
| Indonesia | conventional long form: Republic of Indonesia conventional short form: Indonesia local long form: Republik Indonesia local short form: Indonesia former: Netherlands East Indies, Dutch East Indies |
| Iran | conventional long form: Islamic Republic of Iran conventional short form: Iran local long form: Jomhuri-ye Eslami-ye Iran local short form: Iran former: Persia |