| | Flat Top Mountain, TN | East Ridge, TN | United States |
| Population | 853 | 21,967 | 329,725,481 |
| Female Population | 75.9% | 52.1% | 50.5% |
| Male Population | 24.2% | 47.9% | 49.5% |
| Median Age | 16.7 | 41.2 | 38.4 |
| space3 | | | |
| Population - 2010 | 367 | 21,008 | 309,327,143 |
| Population - 2000 | 442 | 20,640 | 285,036,114 |
| Population - 1990 | 355 | 21,101 | 251,960,433 |
| Pop. 2000 to Now | -9.5% | 2.7% | 15.6% |
| Pop. 1990 to Now | 12.7% | 0.5% | 30.8% |
| space4 | | | |
| Population Density | 49.2 | 2,652.4 | 93.4 |
| Land Area | 17.3 | 8.3 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Flat Top Mountain, TN | East Ridge, TN | United States |
| Age 0 to 4 | 0.0% | 5.7% | 5.9% |
| Age 5 to 9 | 1.5% | 6.3% | 6.1% |
| Age 10 to 14 | 32.0% | 3.7% | 6.6% |
| Age 15 to 17 | 19.9% | 3.4% | 3.9% |
| Age 18 to 20 | 1.5% | 2.4% | 4.0% |
| Age 21 to 24 | 2.6% | 4.3% | 5.2% |
| Age 25 to 34 | 1.5% | 17.1% | 13.8% |
| Age 35 to 44 | 5.7% | 11.7% | 12.9% |
| Age 45 to 54 | 5.3% | 14.2% | 12.6% |
| Age 55 to 59 | 19.7% | 5.8% | 6.7% |
| Age 60 to 64 | 1.3% | 6.8% | 6.3% |
| Age 65 to 74 | 6.2% | 11.2% | 9.6% |
| Age 75 to 84 | 2.1% | 4.6% | 4.5% |
| Age 85 and over | 0.6% | 3.0% | 1.9% |
| space1 | | | |
| Race | | | |
| | Flat Top Mountain, TN | East Ridge, TN | United States |
| White | 99.2% | 70.5% | 59.4% |
| Black | 0.0% | 12.4% | 12.2% |
| Asian | 0.0% | 0.9% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.9% | 0.4% |
| Two or More Races | 0.8% | 2.4% | 3.2% |
| Hispanic | 0.0% | 13.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Flat Top Mountain, TN | East Ridge, TN | United States |
| Married Population | 51.1% | 45.6% | 49.8% |
| Currently Married | 50.6% | 43.3% | 48.0% |
| Married but Separated | 0.5% | 2.3% | 1.8% |
| Single Population | 48.9% | 54.4% | 50.2% |
| Never Married | 39.7% | 32.2% | 33.8% |
| Divorced | 5.6% | 15.9% | 10.8% |
| Widowed | 3.5% | 6.3% | 5.6% |
| space5 | | | |
| Household Size | 4.22 | 2.22 | 2.60 |
| Households | 202 | 9,799 | 124,010,992 |
| Family Households | 165 | 5,388 | 80,755,759 |
| Married couple, w/children | 57.0% | 22.2% | 30.5% |
| Married couple, no children | 30.3% | 49.2% | 42.9% |
| Non Family Households | 37 | 4,411 | 43,255,233 |
| Single householder, w/children | 1.8% | 15.7% | 15.8% |
| Single householder, no children | 10.9% | 12.9% | 10.8% |