Surname begins with

1. a
2. b
3. c
4. d
5. e
6. f
7. g
8. h
9. i
10. j
11. k
12. l
13. m
14. n
15. o
16. p
17. q
18. r
19. s
20. t
21. u
22. v
23. w
24. x
25. y
26. z

1. O'Brien, Lucy
2. O'Brien, Sean
3. O'Byrne, Nicola
4. O'Byrne, Nicola
5. O'Connell, Joanne
6. O'Connor, Bridget
7. O'Connor, Deborah
8. O'Connor, Elizabeth
9. O’Connor, Katherine Tiernan
10. O'Donnell, Bridget
11. O'Dowd, Chris
12. O'Hara, Lauren
13. O'Hara, Mo
14. O'Hara, Natalia
15. O'Hare, Gráinne
16. O’Hart, Sinéad
17. O'Kane, Owen
18. O'Neill, A.D.
19. O'Neill, Amanda
20. O'Neill, Heather Aimee
21. O'Neill, Martin
22. O’Neill, Eamonn
23. O'Reilly, Bill
24. O'Rourke, P. J.
25. O'Shaughnessy, Patrick
26. O'Sullivan, Ronnie
27. Oakley, Phil
28. Oakley, Stu
29. Oates, Joyce Carol
30. Obasanjo, Olusegun
31. Oborne, Martine
32. Odette, Tessonja
33. Ogden, Emily
34. Ogilvie, Sara
35. Ojari, Daniel
36. Olav Lahlum, Hans
37. Oldfield, Matt & Tom
38. Oldfield, Richard
39. Oliver, Abi
40. Oliver, Harry
41. Oliver, Harry
42. Oliver, Joshua
43. Olivotti, Sergio
44. Ollerton, Ollie
45. Olley, Darcie
46. Olney, Peter
47. Olsen, Chris
48. Olson, Jessica S.
49. Olson, Parmy
50. Olusoga, David
51. Olusoga, Kemi
52. Olusoga, Yinka
53. Ondaatje, Michael
54. Orczy, Baroness
55. Ord, Charlotte
56. Orie, Rima
57. Orlando, Jade
58. Orsenna, Érik
59. Ortega, Julio
60. Orwell, George
61. Osborne, George
62. Oseid, Kelsey
63. Osman, Jim
64. Osmond, Richard
65. Ostaseski, Frank
66. Ounsley, Jodie
67. Owen, Amanda
68. Owen, Sid
69. Owens, Lisa
70. Oxlade, Chris
71. Oyemakinde, Tomi
72. Oyeyemi, Helen
73. Ozaki, Yei Theodora
74. Ozawa, Eric