| Country | Country name |
| Bhutan | conventional long form: Kingdom of Bhutan conventional short form: Bhutan local long form: Druk Gyalkhap local short form: Druk Yul |
| Bolivia | conventional long form: Plurinational State of Bolivia conventional short form: Bolivia local long form: Estado Plurinacional de Bolivia local short form: Bolivia |
| Bosnia and Herzegovina | conventional long form: none conventional short form: Bosnia and Herzegovina local long form: none local short form: Bosna i Hercegovina former: People's Republic of Bosnia and Herzegovina, Socialist Republic of Bosnia and Herzegovina |
| Botswana | conventional long form: Republic of Botswana conventional short form: Botswana local long form: Republic of Botswana local short form: Botswana former: Bechuanaland |
| Bouvet Island | conventional long form: none conventional short form: Bouvet Island |
| Brazil | conventional long form: Federative Republic of Brazil conventional short form: Brazil local long form: Republica Federativa do Brasil local short form: Brasil |
| British Indian Ocean Territory | conventional long form: British Indian Ocean Territory conventional short form: none abbreviation: BIOT |
| British Virgin Islands | conventional long form: none conventional short form: British Virgin Islands abbreviation: BVI |
| Brunei | conventional long form: Brunei Darussalam conventional short form: Brunei local long form: Negara Brunei Darussalam local short form: Brunei |
| Bulgaria | conventional long form: Republic of Bulgaria conventional short form: Bulgaria local long form: Republika Balgariya local short form: Balgariya |
| Burkina Faso | conventional long form: none conventional short form: Burkina Faso local long form: none local short form: Burkina Faso former: Upper Volta, Republic of Upper Volta |