| 2009 | |
|---|---|
| Nairobi (City) | 514 943 |
| Meru | 170 912 |
| Kiambu | 158 445 |
| Nakuru | 118 036 |
| Mombasa | 110 955 |
| Kilifi | 93 557 |
| Nyeri | 88 332 |
| Kirinyaga | 51 515 |
| Uasin Gishu | 50 168 |
| Kisumu | 49 658 |
| Kajiado | 48 283 |
| Muranga | 46 955 |
| Taita Taveta | 37 451 |
| Embu | 37 288 |
| Makueni | 36 034 |
| Kwale | 31 361 |
| Nyandarua | 29 594 |
| Machakos | 27 785 |
| Garissa | 24 492 |
| Bungoma | 23 765 |
| Kericho | 23 743 |
| Laikipia | 21 809 |
| Nandi | 17 747 |
| Trans Nzoia | 16 880 |
| Bomet | 16 819 |
| Kakamega | 14 459 |
| Kitui | 13 758 |
| Baringo | 13 623 |
| Elgeyo Marakwet | 13 426 |
| Isiolo | 13 413 |
| Turkana | 12 945 |
| Siaya | 11 698 |
| Narok | 10 241 |
| Homa Bay | 9 969 |
| Kisii | 8 007 |
| Busia | 7 689 |
| West Pokot | 7 353 |
| Samburu | 6 389 |
| Mandera | 5 769 |
| Lamu | 5 030 |
| Tana River | 5 024 |
| Vihiga | 4 155 |
| Marsabit | 3 747 |
| Nyamira | 3 666 |
| Migori | 2 901 |
| Tharaka Nithi | 2 895 |
| Wajir | 1 061 |