| | Middleborough, MA | Kennebunkport, ME | United States |
| Population | 24,219 | 3,607 | 329,725,481 |
| Female Population | 48.5% | 49.6% | 50.5% |
| Male Population | 51.5% | 50.4% | 49.5% |
| Median Age | 43.4 | 54.2 | 38.4 |
| space3 | | | |
| Population - 2010 | 23,146 | 3,474 | 309,327,143 |
| Population - 2000 | 19,941 | 3,720 | 285,036,114 |
| Population - 1990 | 17,867 | 3,356 | 251,960,433 |
| Pop. 2000 to Now | 29.0% | -1.3% | 15.6% |
| Pop. 1990 to Now | 44.0% | 9.4% | 30.8% |
| space4 | | | |
| Population Density | 350.6 | 175.8 | 93.4 |
| Land Area | 69.1 | 20.5 | 3,531,905.4 |
| Water Area | 3.1 | 28.8 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Middleborough, MA | Kennebunkport, ME | United States |
| Age 0 to 4 | 6.1% | 2.1% | 5.9% |
| Age 5 to 9 | 5.7% | 3.4% | 6.1% |
| Age 10 to 14 | 4.5% | 5.2% | 6.6% |
| Age 15 to 17 | 3.5% | 2.6% | 3.9% |
| Age 18 to 20 | 3.2% | 0.8% | 4.0% |
| Age 21 to 24 | 5.3% | 6.6% | 5.2% |
| Age 25 to 34 | 13.7% | 3.9% | 13.8% |
| Age 35 to 44 | 9.4% | 12.3% | 12.9% |
| Age 45 to 54 | 13.3% | 14.1% | 12.6% |
| Age 55 to 59 | 8.1% | 8.5% | 6.7% |
| Age 60 to 64 | 7.1% | 10.3% | 6.3% |
| Age 65 to 74 | 12.8% | 14.7% | 9.6% |
| Age 75 to 84 | 5.6% | 10.3% | 4.5% |
| Age 85 and over | 1.8% | 5.4% | 1.9% |
| space1 | | | |
| Race | | | |
| | Middleborough, MA | Kennebunkport, ME | United States |
| White | 90.1% | 97.0% | 59.4% |
| Black | 1.2% | 0.0% | 12.2% |
| Asian | 1.3% | 0.2% | 5.6% |
| Native American | 0.1% | 0.3% | 0.6% |
| Hawaiian, Pacific Islander | 0.2% | 0.0% | 0.2% |
| Other | 2.3% | 0.0% | 0.4% |
| Two or More Races | 1.8% | 2.2% | 3.2% |
| Hispanic | 3.0% | 0.3% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Middleborough, MA | Kennebunkport, ME | United States |
| Married Population | 49.6% | 51.9% | 49.8% |
| Currently Married | 49.1% | 51.7% | 48.0% |
| Married but Separated | 0.5% | 0.2% | 1.8% |
| Single Population | 50.4% | 48.1% | 50.2% |
| Never Married | 34.4% | 24.3% | 33.8% |
| Divorced | 10.8% | 16.6% | 10.8% |
| Widowed | 5.2% | 7.2% | 5.6% |
| space5 | | | |
| Household Size | 2.44 | 2.17 | 2.60 |
| Households | 9,727 | 1,663 | 124,010,992 |
| Family Households | 6,255 | 901 | 80,755,759 |
| Married couple, w/children | 25.7% | 20.3% | 30.5% |
| Married couple, no children | 47.1% | 67.6% | 42.9% |
| Non Family Households | 3,472 | 762 | 43,255,233 |
| Single householder, w/children | 18.1% | 6.4% | 15.8% |
| Single householder, no children | 9.1% | 5.7% | 10.8% |