| | Andover, CT | Ansonia, CT | United States |
| Population | 2,998 | 18,945 | 329,725,481 |
| Female Population | 50.9% | 51.8% | 50.5% |
| Male Population | 49.1% | 48.2% | 49.5% |
| Median Age | 50 | 42.2 | 38.4 |
| space3 | | | |
| Population - 2010 | 3,304 | 19,276 | 309,327,143 |
| Population - 2000 | 3,036 | 18,554 | 285,036,114 |
| Population - 1990 | 2,540 | 18,403 | 251,960,433 |
| Pop. 2000 to Now | 6.3% | -0.2% | 15.6% |
| Pop. 1990 to Now | 27.1% | 0.7% | 30.8% |
| space4 | | | |
| Population Density | 194.1 | 3,147.5 | 93.4 |
| Land Area | 15.4 | 6.0 | 3,531,905.4 |
| Water Area | 0.2 | 0.2 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Andover, CT | Ansonia, CT | United States |
| Age 0 to 4 | 5.8% | 4.3% | 5.9% |
| Age 5 to 9 | 3.3% | 7.0% | 6.1% |
| Age 10 to 14 | 3.7% | 5.3% | 6.6% |
| Age 15 to 17 | 3.6% | 3.1% | 3.9% |
| Age 18 to 20 | 3.3% | 2.0% | 4.0% |
| Age 21 to 24 | 4.9% | 2.3% | 5.2% |
| Age 25 to 34 | 12.6% | 13.7% | 13.8% |
| Age 35 to 44 | 7.3% | 14.7% | 12.9% |
| Age 45 to 54 | 15.3% | 11.7% | 12.6% |
| Age 55 to 59 | 9.6% | 8.3% | 6.7% |
| Age 60 to 64 | 10.6% | 8.8% | 6.3% |
| Age 65 to 74 | 14.0% | 10.4% | 9.6% |
| Age 75 to 84 | 5.8% | 6.1% | 4.5% |
| Age 85 and over | 0.3% | 2.4% | 1.9% |
| space1 | | | |
| Race | | | |
| | Andover, CT | Ansonia, CT | United States |
| White | 91.0% | 60.3% | 59.4% |
| Black | 1.3% | 10.4% | 12.2% |
| Asian | 1.6% | 1.4% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.3% | 0.4% |
| Two or More Races | 5.1% | 3.2% | 3.2% |
| Hispanic | 1.0% | 24.4% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Andover, CT | Ansonia, CT | United States |
| Married Population | 58.6% | 43.1% | 49.8% |
| Currently Married | 57.4% | 41.9% | 48.0% |
| Married but Separated | 1.2% | 1.2% | 1.8% |
| Single Population | 41.4% | 56.9% | 50.2% |
| Never Married | 27.7% | 35.5% | 33.8% |
| Divorced | 9.4% | 14.6% | 10.8% |
| Widowed | 4.3% | 6.8% | 5.6% |
| space5 | | | |
| Household Size | 2.54 | 2.35 | 2.60 |
| Households | 1,178 | 8,040 | 124,010,992 |
| Family Households | 855 | 5,061 | 80,755,759 |
| Married couple, w/children | 22.1% | 18.8% | 30.5% |
| Married couple, no children | 61.2% | 37.6% | 42.9% |
| Non Family Households | 323 | 2,979 | 43,255,233 |
| Single householder, w/children | 11.0% | 24.3% | 15.8% |
| Single householder, no children | 5.7% | 19.3% | 10.8% |