(Click on the column title to sort by that column)
| # | Catholics | Population | Percent Catholic | Diocese | Year | Source |
|---|---|---|---|---|---|---|
| 1 | 100,000 | 6,200,000 | 1.61% | Athenai {Athens} (Archdiocese) | 2004 | ap2005 |
| 2 | 4,000 | 3,501,000 | .11% | Thessaloniki (Vicariate Apostolic) | 2004 | ap2005 |
| 3 | 3,800 | 1,200,000 | .32% | Corfù, Zante e Cefalonia (Archdiocese) | 2004 | ap2005 |
| 4 | 3,500 | 505,000 | .69% | Crete {Candia} | 2004 | ap2005 |
| 5 | 500 | 205,000 | .24% | Chios | 2004 | ap2005 |
| 6 | 1,500 | 150,000 | 1.00% | Rhodos {Rhodes} (Archdiocese) | 2004 | ap2005 |
| 7 | 4,000 | 58,000 | 6.90% | Naxos, Andros, Tinos e Mykonos (Archdiocese) | 2004 | ap2005 |
| 8 | 6,732 | 31,302 | 21.51% | Syros e Milos | 2004 | ap2005 |
| 9 | 450 | 12,366 | 3.64% | Santorini {Thira} | 2004 | ap2005 |
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