(Click on the column title to sort by that column)
| # | Catholics | Population | Percent Catholic | Diocese | Year | Source |
|---|---|---|---|---|---|---|
| 1 | 1,228,100 | 4,020,100 | 30.55% | Nairobi (Archdiocese) | 2004 | ap2005 |
| 2 | 737,821 | 2,152,535 | 34.28% | Meru | 2004 | ap2005 |
| 3 | 781,799 | 2,104,727 | 37.14% | Machakos | 2004 | ap2005 |
| 4 | 342,123 | 1,988,123 | 17.21% | Kakamega | 2004 | ap2005 |
| 5 | 368,136 | 1,970,000 | 18.69% | Homa Bay | 2004 | ap2005 |
| 6 | 371,631 | 1,871,631 | 19.86% | Kisumu (Archdiocese) | 2004 | ap2005 |
| 7 | 235,700 | 1,804,652 | 13.06% | Mombasa (Archdiocese) | 2004 | ap2005 |
| 8 | 399,624 | 1,800,000 | 22.20% | Kisii | 2004 | ap2005 |
| 9 | 375,965 | 1,560,600 | 24.09% | Eldoret | 2004 | ap2005 |
| 10 | 223,856 | 1,554,850 | 14.40% | Kericho | 2004 | ap2005 |
| 11 | 543,715 | 1,529,817 | 35.54% | Bungoma | 2004 | ap2005 |
| 12 | 230,822 | 1,471,451 | 15.69% | Nakuru | 2004 | ap2005 |
| 13 | 695,830 | 1,441,116 | 48.28% | Muranga | 2004 | ap2005 |
| 14 | 157,000 | 970,000 | 16.19% | Kitale | 2004 | ap2005 |
| 15 | 143,106 | 945,958 | 15.13% | Kitui | 2004 | ap2005 |
| 16 | 74,634 | 942,395 | 7.92% | Ngong | 2004 | ap2005 |
| 17 | 476,870 | 790,327 | 60.34% | Nyeri (Archdiocese) | 2004 | ap2005 |
| 18 | 7,000 | 700,000 | 1.00% | Garissa | 2004 | ap2005 |
| 19 | 181,632 | 672,918 | 26.99% | Nyahururu | 2004 | ap2005 |
| 20 | 21,800 | 539,000 | 4.04% | Malindi | 2004 | ap2005 |
| 21 | 303,877 | 520,000 | 58.44% | Embu | 2004 | ap2005 |
| 22 | 48,759 | 477,000 | 10.22% | Lodwar | 2004 | ap2005 |
| 23 | 22,100 | 201,266 | 10.98% | Marsabit | 2004 | ap2005 |
| 24 | 32,498 | 160,000 | 20.31% | Maralal | 2004 | ap2005 |
| 25 | 27,300 | 116,900 | 23.35% | Isiolo (Vicariate Apostolic) | 2004 | ap2005 |
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