Population classified by religion and nationality 2006
| Nationality | Irish | Non-Irish | UK | Rest of EU | Rest of Europe | Africa | Asia | America | Other National-ities | Not Stated | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Total | 3,706,683 | 419,733 | 112,548 | 163,227 | 24,425 | 35,326 | 46,952 | 21,124 | 16,131 | 45,597 | 4,172,013 |
| Catholic | 3,409,381 | 213,412 | 54,214 | 112,806 | 4,002 | 8,530 | 12,443 | 13,229 | 8,188 | 22,172 | 3,644,965 |
| Church of Ireland (incl. Protestant) | 86,990 | 31,197 | 22,511 | 3,388 | 412 | 2,467 | 648 | 722 | 1,049 | 761 | 118,948 |
| Other Christian Religion | 16,327 | 11,484 | 1,667 | 1,551 | 1,082 | 4,553 | 1,482 | 738 | 411 | 217 | 28,028 |
| Presbyterian | 13,628 | 7,741 | 3,621 | 990 | 263 | 1,649 | 259 | 549 | 410 | 127 | 21,496 |
| Muslim (Islamic) | 9,761 | 21,613 | 620 | 777 | 1,924 | 6,909 | 10,649 | 128 | 606 | 405 | 31,779 |
| Orthodox | 2,881 | 16,845 | 117 | 3,666 | 11,776 | 196 | 731 | 64 | 295 | 268 | 19,994 |
| Methodist | 5,077 | 5,612 | 2,053 | 293 | 52 | 2,330 | 407 | 281 | 196 | 79 | 10,768 |
| Other Stated Religions | 22,497 | 31,118 | 4,167 | 7,284 | 1,824 | 6,337 | 8,792 | 1,866 | 848 | 418 | 54,033 |
| No Religion | 105,356 | 68,444 | 21,851 | 27,529 | 2,101 | 917 | 10,187 | 2,661 | 3,198 | 1,452 | 175,252 |
| Not Stated | 34,785 | 12,267 | 1,727 | 4,943 | 989 | 1,438 | 1,354 | 886 | 930 | 19,698 | 66,750 |