(Click on the column title to sort by that column)
| # | Catholics | Population | Percent Catholic | Diocese | Year | Source |
|---|---|---|---|---|---|---|
| 1 | 1,029,182 | 3,518,627 | 29.25% | Melbourne (Archdiocese) | 2004 | ap2005 |
| 2 | 598,700 | 2,529,154 | 23.67% | Brisbane (Archdiocese) | 2004 | ap2005 |
| 3 | 578,567 | 1,993,236 | 29.03% | Sydney (Archdiocese) | 2004 | ap2005 |
| 4 | 380,010 | 1,427,956 | 26.61% | Perth (Archdiocese) | 2004 | ap2005 |
| 5 | 275,174 | 1,290,786 | 21.32% | Adelaide (Archdiocese) | 2004 | ap2005 |
| 6 | 307,392 | 924,621 | 33.25% | Parramatta | 2004 | ap2005 |
| 7 | 203,969 | 811,406 | 25.14% | Broken Bay | 2004 | ap2005 |
| 8 | 195,669 | 647,912 | 30.20% | Wollongong | 2004 | ap2005 |
| 9 | 147,602 | 602,693 | 24.49% | Maitland-Newcastle | 2004 | ap2005 |
| 10 | 160,700 | 551,400 | 29.14% | Canberra (and Goulburn) (Archdiocese) | 2004 | ap2005 |
| 11 | 87,691 | 472,725 | 18.55% | Hobart (Archdiocese) | 2004 | ap2005 |
| 12 | 105,609 | 441,734 | 23.91% | Lismore | 2004 | ap2005 |
| 13 | 96,877 | 379,851 | 25.50% | Ballarat | 2004 | ap2005 |
| 14 | 92,746 | 372,979 | 24.87% | Sale | 2004 | ap2005 |
| 15 | 95,000 | 372,000 | 25.54% | Rockhampton | 2004 | ap2005 |
| 16 | 91,400 | 341,850 | 26.74% | Sandhurst | 2004 | ap2005 |
| 17 | 50,190 | 257,818 | 19.47% | Bunbury | 2004 | ap2005 |
| 18 | 74,084 | 252,289 | 29.36% | Townsville | 2004 | ap2005 |
| 19 | 59,912 | 235,396 | 25.45% | Cairns | 2004 | ap2005 |
| 20 | 65,912 | 232,900 | 28.30% | Toowoomba | 2004 | ap2005 |
| 21 | 62,000 | 206,000 | 30.10% | Wagga Wagga | 2004 | ap2005 |
| 22 | 67,728 | 203,621 | 33.26% | Bathurst | 2004 | ap2005 |
| 23 | 44,231 | 198,600 | 22.27% | Darwin | 2004 | ap2005 |
| 24 | 28,653 | 166,713 | 17.19% | Port Pirie | 2004 | ap2005 |
| 25 | 47,343 | 161,083 | 29.39% | Armidale | 2004 | ap2005 |
| 26 | 35,904 | 118,257 | 30.36% | Wilcannia-Forbes | 2004 | ap2005 |
| 27 | 27,135 | 114,662 | 23.67% | Geraldton | 2004 | ap2005 |
| 28 | 13,740 | 30,900 | 44.47% | Broome | 2004 | ap2005 |
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