(Click on the column title to sort by that column)
| # | Catholics | Population | Percent Catholic | Diocese | Year | Source |
|---|---|---|---|---|---|---|
| 1 | 732,503 | 857,974 | 85.38% | Nsukka | 2004 | ap2005 |
| 2 | 401,506 | 510,623 | 78.63% | Ahiara | 2004 | ap2005 |
| 3 | 458,302 | 687,453 | 66.67% | Nnewi | 2004 | ap2005 |
| 4 | 1,373,660 | 2,060,490 | 66.67% | Onitsha (Archdiocese) | 2004 | ap2005 |
| 5 | 562,837 | 881,385 | 63.86% | Orlu | 2004 | ap2005 |
| 6 | 360,000 | 600,000 | 60.00% | Awgu | 2005 | bul08Jul2005 |
| 7 | 840,000 | 1,400,000 | 60.00% | Enugu | 2005 | bul08Jul2005 |
| 8 | 658,009 | 1,247,637 | 52.74% | Awka | 2004 | ap2005 |
| 9 | 2,164,083 | 4,524,387 | 47.83% | Lagos (Archdiocese) | 2004 | ap2005 |
| 10 | 1,380,790 | 3,005,568 | 45.94% | Makurdi | 2004 | ap2005 |
| 11 | 823,483 | 2,001,838 | 41.14% | Okigwe | 2004 | ap2005 |
| 12 | 670,986 | 1,693,329 | 39.63% | Owerri (Archdiocese) | 2004 | ap2005 |
| 13 | 598,028 | 1,779,856 | 33.60% | Uyo | 1997 | ap2004 |
| 14 | 292,366 | 951,117 | 30.74% | Issele-Uku | 2004 | ap2005 |
| 15 | 572,147 | 2,236,135 | 25.59% | Aba | 2004 | ap2005 |
| 16 | 250,000 | 1,080,247 | 23.14% | Kafanchan | 2004 | ap2005 |
| 17 | 199,000 | 884,209 | 22.51% | Umuahia | 2004 | ap2005 |
| 18 | 332,373 | 1,536,294 | 21.63% | Ogoja | 2004 | ap2005 |
| 19 | 331,000 | 1,675,000 | 19.76% | Abakaliki | 2004 | ap2005 |
| 20 | 502,437 | 2,843,105 | 17.67% | Otukpo | 2004 | ap2005 |
| 21 | 507,164 | 3,107,225 | 16.32% | Jos (Archdiocese) | 2004 | ap2005 |
| 22 | 343,800 | 2,882,410 | 11.93% | Benin City (Archdiocese) | 2004 | ap2005 |
| 23 | 98,552 | 908,028 | 10.85% | Ikot Ekpene | 2004 | ap2005 |
| 24 | 218,466 | 2,143,956 | 10.19% | Ekiti | 2004 | ap2005 |
| 25 | 189,686 | 1,867,241 | 10.16% | Lafia | 2004 | ap2005 |
| 26 | 129,763 | 1,342,480 | 9.67% | Idah | 2004 | ap2005 |
| 27 | 252,653 | 2,832,299 | 8.92% | Jalingo | 2004 | ap2005 |
| 28 | 200,000 | 2,300,000 | 8.70% | Abuja (Archdiocese) | 2004 | ap2005 |
| 29 | 191,004 | 2,303,267 | 8.29% | Calabar (Archdiocese) | 2004 | ap2005 |
| 30 | 65,000 | 800,200 | 8.12% | Auchi | 2004 | ap2005 |
| 31 | 348,650 | 4,421,430 | 7.89% | Ibadan (Archdiocese) | 2004 | ap2005 |
| 32 | 156,890 | 2,135,240 | 7.35% | Yola | 2004 | ap2005 |
| 33 | 186,298 | 2,614,857 | 7.12% | Warri | 2004 | ap2005 |
| 34 | 323,076 | 4,951,310 | 6.53% | Kaduna (Archdiocese) | 2004 | ap2005 |
| 35 | 198,722 | 3,674,692 | 5.41% | Ondo | 2004 | ap2005 |
| 36 | 218,412 | 4,521,429 | 4.83% | Port Harcourt | 2004 | ap2005 |
| 37 | 68,950 | 1,839,927 | 3.75% | Zaria | 2004 | ap2005 |
| 38 | 67,383 | 2,290,344 | 2.94% | Ijebu-Ode | 2004 | ap2005 |
| 39 | 65,858 | 2,267,107 | 2.90% | Minna | 2004 | ap2005 |
| 40 | 53,503 | 1,935,448 | 2.76% | Abeokuta | 2004 | ap2005 |
| 41 | 40,000 | 1,500,000 | 2.67% | Osogbo | 2004 | ap2005 |
| 42 | 36,507 | 1,465,530 | 2.49% | Lokoja | 2004 | ap2005 |
| 43 | 109,000 | 5,200,000 | 2.10% | Maiduguri | 2004 | ap2005 |
| 44 | 25,500 | 1,260,000 | 2.02% | Ilorin | 2004 | ap2005 |
| 45 | 25,595 | 1,300,000 | 1.97% | Kontagora (Vicariate Apostolic) | 2004 | ap2005 |
| 46 | 30,200 | 2,031,660 | 1.49% | Oyo | 2004 | ap2005 |
| 47 | 123,984 | 8,688,604 | 1.43% | Kano | 2004 | ap2005 |
| 48 | 68,699 | 5,406,530 | 1.27% | Bauchi | 2004 | ap2005 |
| 49 | 19,000 | 1,836,000 | 1.03% | Bomadi (Vicariate Apostolic) | 2003 | ap2004 |
| 50 | 60,554 | 12,251,910 | .49% | Sokoto | 2004 | ap2005 |
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