| County : | Jefferson County |
| State : | Missouri (MO) |
| Land Area : | 656.63 sq mi |
| Water Area : | 7.66 sq mi |
| Latitude : | 38.2574144 |
| Longitude : | -90.5431382 |
| Population (2010): | 218,733 |
| Population Estimate (2012) : | 218,628 |
| Population Density : | 333.12/sq mi |
| Housing Units (2012) : | 87,626 |
| Median Household Income (2012) : | $55,743 (Missouri : $47,333, USA : $53,046) |
| Median Family Income (2012) : | $64,956 (Missouri : $59,395, USA : $64,585) |
| Median House Price (2012) : | $154,200 (Missouri : $138,400, USA : $181,400) |
Jefferson County Cities / Towns
| Arnold City (20,808) | Barnhart (5,682) | Byrnes Mill City (2,781) |
| Cedar Hill (1,721) | Cedar Hill Lakes Village (237) | Crystal City (4,855) |
| De Soto City (6,400) | Festus City (11,602) | Herculaneum City (3,468) |
| High Ridge (4,305) | Hillsboro City (2,821) | Horine (821) |
| Imperial (4,709) | Kimmswick City (157) | Labarque Creek (1,558) |
| Lake Tekakwitha Village (254) | Murphy (8,690) | Olympian Village City (774) |
| Parkdale Village (170) | Peaceful Village Village (9) | Pevely City (5,484) |
| Scotsdale Town (222) |
Jefferson County Zip Codes
| 63010 (35,439) | 63012 (9,973) | 63015 (2,076) |
| 63016 (7,582) | 63019 (4,449) | 63020 (20,714) |
| 63023 (5,831) | 63025 (13,854) | 63026 (44,124) |
| 63028 (26,413) | 63041 (534) | 63047 (31) |
| 63048 (3,357) | 63049 (15,896) | 63050 (15,716) |
| 63051 (14,495) | 63052 (26,431) | 63053 (62) |
| 63057 (56) | 63069 (15,647) | 63070 (7,438) |
| 63072 (3,194) | 63087 (769) | 63627 (2,937) |
| 63628 (16,014) |