| Name | # Entries |
|---|---|
| I | 2733 |
| Ison | 439 |
| Islam Islam | 360 |
| Issa Issa | 278 |
| Ilic | 236 |
| Ives | 209 |
| Ivers | 195 |
| Iacono | 166 |
| Im | 152 |
| Ioannidis | 147 |
| Ingls | 136 |
| Ivanovic | 132 |
| Ingleton | 130 |
| Irani | 101 |
| Ingold | 98 |
| Imber | 97 |
| Itchens | 96 |
| Iuliano | 96 |
| Ishak | 95 |
| Iredale | 94 |
| Ing | 94 |
| Ivanovski | 93 |
| Ind | 91 |
| Inskip | 90 |
| Ian | 82 |
| Iverson | 82 |
| Ibrahimi | 79 |
| Iliopoulos | 79 |
| Ioppolo | 79 |
| Iskander | 77 |
| Iannello | 75 |
| Ivkovic | 74 |
| Irlam | 72 |
| Iaria | 71 |
| Ibbott | 71 |
| Ingles' | 70 |
| Ianni | 68 |
| Isbester | 66 |
| Iselin | 65 |
| Ieraci | 64 |
| Iseppi | 64 |
| Issac | 63 |
| Iskra | 63 |
| Iverach | 62 |
| Inness | 61 |
| Izzo | 61 |
| Iorio | 59 |
| Ippolito | 56 |
| Inglese | 56 |
| Iglesias | 55 |
| Ible | 55 |
| Iffland | 54 |
| Iliadis | 52 |
| Is Hak | 52 |
| Itzstein | 51 |
| Iezzi | 51 |
| Iemma | 50 |
| Ingersole | 50 |
| Ianson | 48 |
| I I | 48 |
| Insch | 48 |
| Iacuone | 47 |
| Ishac | 47 |
| Iannella | 46 |
| Ida | 45 |
| Ignacio | 45 |
| Irawan | 45 |
| Ibraham | 44 |
| Ierace | 44 |
| Inzitari | 44 |
| Isa | 44 |
| Iannelli | 43 |
| Igoe | 43 |
| Ianna | 42 |
| Ibanez | 42 |