• Babbage, Dennis 1, 2, 3
• Bacon, Francis 1
• Balance, Mrs 1, 2
• Bassières, Colonel 1
• Batey, Keith 1, 2, 3, 4, 5, 6
• Batey, Mavis see Lever, Mavis
• BBC, Spy 1
• Beatty, Admiral Sir David 1
• Bell, Edward 1
• Bernstorff, Johann von 1
• Bertrand, Gustave 1, 2, 3, 4, 5, 6, 7
• Birch, Frank
  • Alice in ID25 1
  • codebreaking 1, 2
  • A Contribution to the History of German Naval Warfare 1914 1, 2
  • and DK 1, 2
  • marriage 1
  • Operation Ruthless 1
• Bletchley Park 1, 2
• Bodsworth, Wilfred 1, 2, 3, 4
• ‘boil’ technique 1, 2g
• Bolliday Bango 1
• bombes 1, 2, 3g
• bomby 1, 2, 3, 4, 5g
• The Book of Acrostics (Ronnie Knox) 1
• boxing 1, 2, 3g
• Braquenié, Henri 1, 2, 3, 4, 5
• Brewster, Pam 1
• Bruford, Professor Walter 1
• ‘Brutus’ (Roman Garby-Czerniawski) 1
• ‘buttoning-up’ 1, 2, 3, 4, 5g