| | Sylvania, AL | Huntsville, AL | United States |
| Population | 1,848 | 210,081 | 329,725,481 |
| Female Population | 55.4% | 51.3% | 50.5% |
| Male Population | 44.6% | 48.7% | 49.5% |
| Median Age | 38.3 | 37.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,827 | 180,926 | 309,327,143 |
| Population - 2000 | 1,186 | 158,216 | 285,036,114 |
| Population - 1990 | 932 | 159,789 | 251,960,433 |
| Pop. 2000 to Now | 56.8% | 28.3% | 15.6% |
| Pop. 1990 to Now | 99.6% | 27.0% | 30.8% |
| space4 | | | |
| Population Density | 209.6 | 980.1 | 93.4 |
| Land Area | 8.8 | 214.4 | 3,531,905.4 |
| Water Area | 0.2 | 1.4 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Sylvania, AL | Huntsville, AL | United States |
| Age 0 to 4 | 3.8% | 5.8% | 5.9% |
| Age 5 to 9 | 9.8% | 5.7% | 6.1% |
| Age 10 to 14 | 10.2% | 5.4% | 6.6% |
| Age 15 to 17 | 2.4% | 2.9% | 3.9% |
| Age 18 to 20 | 1.6% | 4.8% | 4.0% |
| Age 21 to 24 | 2.8% | 7.1% | 5.2% |
| Age 25 to 34 | 13.0% | 15.5% | 13.8% |
| Age 35 to 44 | 16.8% | 12.1% | 12.9% |
| Age 45 to 54 | 13.0% | 11.5% | 12.6% |
| Age 55 to 59 | 7.6% | 6.8% | 6.7% |
| Age 60 to 64 | 4.0% | 6.2% | 6.3% |
| Age 65 to 74 | 10.9% | 9.3% | 9.6% |
| Age 75 to 84 | 3.4% | 4.8% | 4.5% |
| Age 85 and over | 0.6% | 2.1% | 1.9% |
| space1 | | | |
| Race | | | |
| | Sylvania, AL | Huntsville, AL | United States |
| White | 83.1% | 57.0% | 59.4% |
| Black | 0.0% | 30.6% | 12.2% |
| Asian | 0.0% | 2.2% | 5.6% |
| Native American | 1.2% | 0.3% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.1% | 0.2% |
| Other | 0.0% | 0.1% | 0.4% |
| Two or More Races | 7.8% | 3.3% | 3.2% |
| Hispanic | 7.8% | 6.4% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Sylvania, AL | Huntsville, AL | United States |
| Married Population | 55.9% | 45.7% | 49.8% |
| Currently Married | 48.2% | 43.6% | 48.0% |
| Married but Separated | 7.7% | 2.1% | 1.8% |
| Single Population | 44.1% | 54.3% | 50.2% |
| Never Married | 20.7% | 36.1% | 33.8% |
| Divorced | 13.5% | 12.4% | 10.8% |
| Widowed | 9.9% | 5.9% | 5.6% |
| space5 | | | |
| Household Size | 2.67 | 2.21 | 2.60 |
| Households | 691 | 91,048 | 124,010,992 |
| Family Households | 507 | 51,704 | 80,755,759 |
| Married couple, w/children | 31.4% | 23.3% | 30.5% |
| Married couple, no children | 26.4% | 45.6% | 42.9% |
| Non Family Households | 184 | 39,344 | 43,255,233 |
| Single householder, w/children | 30.2% | 19.0% | 15.8% |
| Single householder, no children | 12.0% | 12.1% | 10.8% |