B
- Back Cup: a fictional island in the Bahamas, hideout of the pirate Ker Karraje in Jules Verne's novel Facing the Flag.
- Bahavia: a parody of Bavaria where the Paroom family e.g. Meena Paroom come from in the Disney channel original series Cory in the House
- Balfe: the island setting on the 1972 movie Doomwatch
- Bali Ha'i: the mysterious island in South Pacific and Tales of the South Pacific
- Balamb Island: from Final Fantasy VIII
- Battle Frontier: from Pokémon Emerald
- Beer Island: a mythical land where Linux power management works reliably.
- Benne Seed Island: an island off the coast of South Carolina near Charleston, where Polly O'Keefe and her family live in several novels by Madeleine L'Engle
- Bensalem: from New Atlantis by Francis Bacon
- Besaid: from Final Fantasy X and Final Fantasy X-2
- Bikanel: from Final Fantasy X and Final Fantasy X-2
- Binghuo Island (literally: Ice and Fire Island): from the wuxia novel The Heavenly Sword and the Dragon Saber by Jin Yong
- The Black Island from Tintin by Hergé
- Blackhawk Island: Secret base of the Blackhawks during World War II and beyond.
- Island of the Blue Dolphins: (based on San Nicolas Island) from the book by Scott O'Dell.
- Blefuscu: from the novel Gulliver's Travels by Jonathan Swift
- Booty Island: a pirate island in the Caribbean in the game Monkey Island 2: LeChuck's Revenge, part of the Tri-Island area (governed by Elaine Marley)
- Britannula: setting of the novel The Fixed Period by Anthony Trollope
Read more about this topic: List Of Fictional Islands