| | High Ridge, MO | Festus, MO | United States |
| Population | 4,201 | 12,609 | 329,725,481 |
| Female Population | 51.5% | 53.1% | 50.5% |
| Male Population | 48.5% | 46.9% | 49.5% |
| Median Age | 46.1 | 36.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 4,808 | 11,599 | 309,327,143 |
| Population - 2000 | 4,236 | 9,660 | 285,036,114 |
| Population - 1990 | 4,423 | 8,105 | 251,960,433 |
| Pop. 2000 to Now | -6.1% | 25.4% | 15.6% |
| Pop. 1990 to Now | -10.1% | 49.5% | 30.8% |
| space4 | | | |
| Population Density | 1,104.9 | 2,200.9 | 93.4 |
| Land Area | 3.8 | 5.7 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | High Ridge, MO | Festus, MO | United States |
| Age 0 to 4 | 2.7% | 8.0% | 5.9% |
| Age 5 to 9 | 7.3% | 7.7% | 6.1% |
| Age 10 to 14 | 6.9% | 7.6% | 6.6% |
| Age 15 to 17 | 2.9% | 1.1% | 3.9% |
| Age 18 to 20 | 5.1% | 4.1% | 4.0% |
| Age 21 to 24 | 2.1% | 5.1% | 5.2% |
| Age 25 to 34 | 7.2% | 14.4% | 13.8% |
| Age 35 to 44 | 14.9% | 13.4% | 12.9% |
| Age 45 to 54 | 17.9% | 12.0% | 12.6% |
| Age 55 to 59 | 8.3% | 4.6% | 6.7% |
| Age 60 to 64 | 8.5% | 6.7% | 6.3% |
| Age 65 to 74 | 8.0% | 9.7% | 9.6% |
| Age 75 to 84 | 4.5% | 3.6% | 4.5% |
| Age 85 and over | 3.8% | 2.2% | 1.9% |
| space1 | | | |
| Race | | | |
| | High Ridge, MO | Festus, MO | United States |
| White | 92.6% | 88.1% | 59.4% |
| Black | 0.4% | 2.4% | 12.2% |
| Asian | 1.0% | 0.7% | 5.6% |
| Native American | 0.0% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 5.8% | 4.1% | 3.2% |
| Hispanic | 0.2% | 4.6% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | High Ridge, MO | Festus, MO | United States |
| Married Population | 58.4% | 50.4% | 49.8% |
| Currently Married | 55.9% | 49.1% | 48.0% |
| Married but Separated | 2.5% | 1.3% | 1.8% |
| Single Population | 41.6% | 49.6% | 50.2% |
| Never Married | 24.4% | 25.1% | 33.8% |
| Divorced | 10.5% | 15.9% | 10.8% |
| Widowed | 6.7% | 8.5% | 5.6% |
| space5 | | | |
| Household Size | 2.51 | 2.52 | 2.60 |
| Households | 1,660 | 4,958 | 124,010,992 |
| Family Households | 1,106 | 3,320 | 80,755,759 |
| Married couple, w/children | 32.1% | 31.4% | 30.5% |
| Married couple, no children | 45.5% | 37.3% | 42.9% |
| Non Family Households | 554 | 1,638 | 43,255,233 |
| Single householder, w/children | 9.1% | 15.7% | 15.8% |
| Single householder, no children | 13.3% | 15.7% | 10.8% |