| | Hamilton, MT | Fort Benton, MT | United States |
| Population | 4,632 | 1,396 | 329,725,481 |
| Female Population | 56.1% | 48.4% | 50.5% |
| Male Population | 43.9% | 51.6% | 49.5% |
| Median Age | 48.5 | 38.4 | 38.4 |
| space3 | | | |
| Population - 2010 | 4,288 | 1,464 | 309,327,143 |
| Population - 2000 | 3,705 | 1,594 | 285,036,114 |
| Population - 1990 | 2,737 | 1,660 | 251,960,433 |
| Pop. 2000 to Now | 36.5% | -9.5% | 15.6% |
| Pop. 1990 to Now | 84.7% | -13.1% | 30.8% |
| space4 | | | |
| Population Density | 1,910.9 | 608.8 | 93.4 |
| Land Area | 2.4 | 2.3 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Hamilton, MT | Fort Benton, MT | United States |
| Age 0 to 4 | 6.7% | 4.6% | 5.9% |
| Age 5 to 9 | 2.4% | 9.2% | 6.1% |
| Age 10 to 14 | 2.2% | 6.9% | 6.6% |
| Age 15 to 17 | 2.3% | 5.6% | 3.9% |
| Age 18 to 20 | 1.6% | 0.0% | 4.0% |
| Age 21 to 24 | 4.9% | 5.4% | 5.2% |
| Age 25 to 34 | 10.0% | 11.6% | 13.8% |
| Age 35 to 44 | 16.0% | 15.0% | 12.9% |
| Age 45 to 54 | 11.1% | 8.2% | 12.6% |
| Age 55 to 59 | 5.9% | 3.0% | 6.7% |
| Age 60 to 64 | 6.6% | 6.7% | 6.3% |
| Age 65 to 74 | 14.1% | 12.0% | 9.6% |
| Age 75 to 84 | 8.8% | 7.9% | 4.5% |
| Age 85 and over | 7.6% | 3.9% | 1.9% |
| space1 | | | |
| Race | | | |
| | Hamilton, MT | Fort Benton, MT | United States |
| White | 91.3% | 94.6% | 59.4% |
| Black | 0.0% | 0.0% | 12.2% |
| Asian | 0.8% | 0.2% | 5.6% |
| Native American | 1.8% | 0.4% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 2.1% | 2.8% | 3.2% |
| Hispanic | 4.0% | 1.9% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Hamilton, MT | Fort Benton, MT | United States |
| Married Population | 40.5% | 51.4% | 49.8% |
| Currently Married | 39.7% | 48.9% | 48.0% |
| Married but Separated | 0.8% | 2.5% | 1.8% |
| Single Population | 59.5% | 48.6% | 50.2% |
| Never Married | 23.6% | 29.7% | 33.8% |
| Divorced | 21.3% | 5.5% | 10.8% |
| Widowed | 14.6% | 13.4% | 5.6% |
| space5 | | | |
| Household Size | 1.68 | 2.46 | 2.60 |
| Households | 2,652 | 556 | 124,010,992 |
| Family Households | 1,155 | 320 | 80,755,759 |
| Married couple, w/children | 22.2% | 41.3% | 30.5% |
| Married couple, no children | 48.4% | 41.3% | 42.9% |
| Non Family Households | 1,497 | 236 | 43,255,233 |
| Single householder, w/children | 15.5% | 14.4% | 15.8% |
| Single householder, no children | 13.9% | 3.1% | 10.8% |