| | Gallatin, MO | Liberty, MO | United States |
| Population | 1,597 | 30,129 | 329,725,481 |
| Female Population | 51.0% | 50.1% | 50.5% |
| Male Population | 49.0% | 49.9% | 49.5% |
| Median Age | 40.3 | 36.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,790 | 29,320 | 309,327,143 |
| Population - 2000 | 1,789 | 26,232 | 285,036,114 |
| Population - 1990 | 1,864 | 20,459 | 251,960,433 |
| Pop. 2000 to Now | -1.6% | 23.6% | 15.6% |
| Pop. 1990 to Now | -5.5% | 58.5% | 30.8% |
| space4 | | | |
| Population Density | 581.2 | 1,045.0 | 93.4 |
| Land Area | 2.7 | 28.8 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Gallatin, MO | Liberty, MO | United States |
| Age 0 to 4 | 7.0% | 6.8% | 5.9% |
| Age 5 to 9 | 5.3% | 6.8% | 6.1% |
| Age 10 to 14 | 7.8% | 8.2% | 6.6% |
| Age 15 to 17 | 4.5% | 4.6% | 3.9% |
| Age 18 to 20 | 6.6% | 3.9% | 4.0% |
| Age 21 to 24 | 3.1% | 4.6% | 5.2% |
| Age 25 to 34 | 9.8% | 12.6% | 13.8% |
| Age 35 to 44 | 10.0% | 14.0% | 12.9% |
| Age 45 to 54 | 13.6% | 11.1% | 12.6% |
| Age 55 to 59 | 4.3% | 7.3% | 6.7% |
| Age 60 to 64 | 5.6% | 6.9% | 6.3% |
| Age 65 to 74 | 13.0% | 8.2% | 9.6% |
| Age 75 to 84 | 6.1% | 3.4% | 4.5% |
| Age 85 and over | 3.4% | 1.5% | 1.9% |
| space1 | | | |
| Race | | | |
| | Gallatin, MO | Liberty, MO | United States |
| White | 93.5% | 85.0% | 59.4% |
| Black | 0.0% | 4.6% | 12.2% |
| Asian | 0.2% | 1.5% | 5.6% |
| Native American | 0.2% | 0.3% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.1% | 0.4% |
| Two or More Races | 3.1% | 2.9% | 3.2% |
| Hispanic | 3.0% | 5.5% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Gallatin, MO | Liberty, MO | United States |
| Married Population | 52.1% | 54.9% | 49.8% |
| Currently Married | 50.1% | 53.2% | 48.0% |
| Married but Separated | 2.0% | 1.7% | 1.8% |
| Single Population | 47.9% | 45.1% | 50.2% |
| Never Married | 24.1% | 27.4% | 33.8% |
| Divorced | 16.8% | 12.9% | 10.8% |
| Widowed | 7.0% | 4.8% | 5.6% |
| space5 | | | |
| Household Size | 2.28 | 2.65 | 2.60 |
| Households | 686 | 10,928 | 124,010,992 |
| Family Households | 404 | 7,505 | 80,755,759 |
| Married couple, w/children | 35.9% | 35.4% | 30.5% |
| Married couple, no children | 42.3% | 42.6% | 42.9% |
| Non Family Households | 282 | 3,423 | 43,255,233 |
| Single householder, w/children | 16.6% | 15.6% | 15.8% |
| Single householder, no children | 5.2% | 6.5% | 10.8% |