| County : | St. Mary Parish |
| State : | Louisiana (LA) |
| Land Area : | 555.38 sq mi |
| Water Area : | 564.04 sq mi |
| Latitude : | 29.6293488 |
| Longitude : | -91.4638037 |
| Population (2010): | 54,650 |
| Population Estimate (2012) : | 54,285 |
| Population Density : | 98.40/sq mi |
| Housing Units (2012) : | 23,028 |
| Median Household Income (2012) : | $40,738 (Louisiana : $44,673, USA : $53,046) |
| Median Family Income (2012) : | $48,064 (Louisiana : $56,047, USA : $64,585) |
| Median House Price (2012) : | $90,600 (Louisiana : $137,700, USA : $181,400) |
St. Mary Parish Cities / Towns
| Amelia (2,459) | Baldwin Town (2,436) | Bayou Vista (4,652) |
| Berwick Town (4,946) | Charenton (1,903) | Franklin City (7,660) |
| Glencoe (211) | Morgan City (12,404) | Patterson City (6,112) |
| Siracusaville (422) | Sorrel (766) |
St. Mary Parish Zip Codes
| 70340 (109) | 70342 (4,979) | 70380 (22,928) |
| 70392 (8,456) | 70514 (2,545) | 70523 (906) |
| 70538 (14,844) | 70544 (11,677) |