| 2006 | |
|---|---|
| Nairobi (City) | 416 899 |
| Bungoma | 292 568 |
| Machakos | 251 663 |
| Nakuru | 244 641 |
| Makueni | 220 350 |
| Kiambu | 196 021 |
| Nandi | 190 869 |
| Trans Nzoia | 171 909 |
| Kwale | 163 773 |
| Kilifi | 154 848 |
| Uasin Gishu | 152 391 |
| Kitui | 152 314 |
| Mombasa | 149 034 |
| Kakamega | 148 803 |
| Nyeri | 140 459 |
| Vihiga | 138 408 |
| Busia | 136 102 |
| Narok | 135 815 |
| Migori | 131 822 |
| Siaya | 130 632 |
| Kisumu | 128 579 |
| Nyandarua | 126 543 |
| Bomet | 123 390 |
| Turkana | 122 883 |
| Wajir | 119 153 |
| Kisii | 118 161 |
| Nyamira | 116 411 |
| Garissa | 113 114 |
| Kajiado | 110 961 |
| Laikipia | 100 346 |
| Kericho | 98 821 |
| Kirinyaga | 96 239 |
| West Pokot | 94 885 |
| Mandera | 89 041 |
| Baringo | 82 527 |
| Tana River | 75 367 |
| Homa Bay | 70 945 |
| Embu | 63 788 |
| Taita Taveta | 63 726 |
| Muranga | 62 266 |
| Samburu | 60 750 |
| Marsabit | 37 843 |
| Isiolo | 28 062 |
| Lamu | 18 279 |