| City : | Monmouth City |
| County : | Beauregard Parish, Warren County |
| State : | Illinois (IL) |
| | |
| Land Area : | 4.21 sq mi |
| Water Area : | 0.02 sq mi |
| Latitude : | 40.9144620 |
| Longitude : | -90.6414089 |
| | |
| Population (2010): | 9,444 |
| Population Estimate (2012) : | 9,659 |
| Population Density : | 2,244.19/sq mi |
| Housing Units (2012) : | 3,792 |
| Median Household Income (2012) : | $32,695 (Illinois : $56,853, USA : $53,046) |
| Median Family Income (2012) : | $44,466 (Illinois : $70,144, USA : $64,585) |
| Median House Price (2012) : | $77,600 (Illinois : $190,800, USA : $181,400) |