| | Deep River, CT | Middletown, CT | United States |
| Population | 4,473 | 47,164 | 329,725,481 |
| Female Population | 50.5% | 51.5% | 50.5% |
| Male Population | 49.5% | 48.5% | 49.5% |
| Median Age | 48.3 | 39.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 4,625 | 47,659 | 309,327,143 |
| Population - 2000 | 4,610 | 43,167 | 285,036,114 |
| Population - 1990 | 4,332 | 42,762 | 251,960,433 |
| Pop. 2000 to Now | -4.1% | 6.6% | 15.6% |
| Pop. 1990 to Now | 2.0% | 7.6% | 30.8% |
| space4 | | | |
| Population Density | 331.0 | 1,149.8 | 93.4 |
| Land Area | 13.5 | 41.0 | 3,531,905.4 |
| Water Area | 0.7 | 1.3 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Deep River, CT | Middletown, CT | United States |
| Age 0 to 4 | 3.2% | 3.9% | 5.9% |
| Age 5 to 9 | 1.9% | 4.5% | 6.1% |
| Age 10 to 14 | 5.3% | 4.4% | 6.6% |
| Age 15 to 17 | 10.4% | 2.7% | 3.9% |
| Age 18 to 20 | 1.7% | 7.2% | 4.0% |
| Age 21 to 24 | 2.7% | 6.9% | 5.2% |
| Age 25 to 34 | 9.0% | 15.7% | 13.8% |
| Age 35 to 44 | 10.8% | 11.1% | 12.9% |
| Age 45 to 54 | 21.4% | 12.4% | 12.6% |
| Age 55 to 59 | 7.3% | 7.8% | 6.7% |
| Age 60 to 64 | 6.0% | 7.1% | 6.3% |
| Age 65 to 74 | 15.9% | 9.1% | 9.6% |
| Age 75 to 84 | 3.5% | 4.8% | 4.5% |
| Age 85 and over | 1.0% | 2.3% | 1.9% |
| space1 | | | |
| Race | | | |
| | Deep River, CT | Middletown, CT | United States |
| White | 90.2% | 66.2% | 59.4% |
| Black | 1.6% | 13.3% | 12.2% |
| Asian | 0.7% | 5.6% | 5.6% |
| Native American | 0.0% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.1% | 0.4% |
| Two or More Races | 1.3% | 3.9% | 3.2% |
| Hispanic | 6.2% | 10.9% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Deep River, CT | Middletown, CT | United States |
| Married Population | 54.8% | 39.5% | 49.8% |
| Currently Married | 53.3% | 38.8% | 48.0% |
| Married but Separated | 1.5% | 0.7% | 1.8% |
| Single Population | 45.2% | 60.5% | 50.2% |
| Never Married | 26.8% | 42.1% | 33.8% |
| Divorced | 15.2% | 12.9% | 10.8% |
| Widowed | 3.2% | 5.4% | 5.6% |
| space5 | | | |
| Household Size | 2.16 | 2.14 | 2.60 |
| Households | 2,061 | 20,089 | 124,010,992 |
| Family Households | 1,301 | 10,531 | 80,755,759 |
| Married couple, w/children | 34.1% | 22.8% | 30.5% |
| Married couple, no children | 47.4% | 46.7% | 42.9% |
| Non Family Households | 760 | 9,558 | 43,255,233 |
| Single householder, w/children | 18.5% | 18.1% | 15.8% |
| Single householder, no children | 0.0% | 12.4% | 10.8% |