| | Sagaponack, NY | Amagansett, NY | United States |
| Population | 247 | 663 | 329,725,481 |
| Female Population | 51.8% | 59.3% | 50.5% |
| Male Population | 48.2% | 40.7% | 49.5% |
| Median Age | 63.8 | 62.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 314 | 894 | 309,327,143 |
| Population - 2000 | 582 | 1,067 | 285,036,114 |
| Population - 1990 | 311 | 914 | 251,960,433 |
| Pop. 2000 to Now | -44.5% | -24.4% | 15.6% |
| Pop. 1990 to Now | 3.9% | -11.7% | 30.8% |
| space4 | | | |
| Population Density | 56.0 | 101.6 | 93.4 |
| Land Area | 4.4 | 6.5 | 3,531,905.4 |
| Water Area | 0.2 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Sagaponack, NY | Amagansett, NY | United States |
| Age 0 to 4 | 0.0% | 2.7% | 5.9% |
| Age 5 to 9 | 0.0% | 0.0% | 6.1% |
| Age 10 to 14 | 3.2% | 1.8% | 6.6% |
| Age 15 to 17 | 4.0% | 0.0% | 3.9% |
| Age 18 to 20 | 4.5% | 4.2% | 4.0% |
| Age 21 to 24 | 3.2% | 5.4% | 5.2% |
| Age 25 to 34 | 6.1% | 6.2% | 13.8% |
| Age 35 to 44 | 8.5% | 2.7% | 12.9% |
| Age 45 to 54 | 2.4% | 12.8% | 12.6% |
| Age 55 to 59 | 10.9% | 8.0% | 6.7% |
| Age 60 to 64 | 10.5% | 14.9% | 6.3% |
| Age 65 to 74 | 22.3% | 29.3% | 9.6% |
| Age 75 to 84 | 18.6% | 9.7% | 4.5% |
| Age 85 and over | 5.7% | 2.3% | 1.9% |
| space1 | | | |
| Race | | | |
| | Sagaponack, NY | Amagansett, NY | United States |
| White | 96.8% | 95.0% | 59.4% |
| Black | 0.0% | 0.3% | 12.2% |
| Asian | 0.0% | 0.0% | 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 | 0.0% | 0.0% | 3.2% |
| Hispanic | 3.2% | 4.4% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Sagaponack, NY | Amagansett, NY | United States |
| Married Population | 48.1% | 62.6% | 49.8% |
| Currently Married | 45.6% | 61.5% | 48.0% |
| Married but Separated | 2.5% | 1.1% | 1.8% |
| Single Population | 51.9% | 37.4% | 50.2% |
| Never Married | 27.2% | 17.4% | 33.8% |
| Divorced | 5.9% | 13.0% | 10.8% |
| Widowed | 18.8% | 7.1% | 5.6% |
| space5 | | | |
| Household Size | 2.04 | 2.02 | 2.60 |
| Households | 121 | 323 | 124,010,992 |
| Family Households | 69 | 195 | 80,755,759 |
| Married couple, w/children | 2.9% | 5.1% | 30.5% |
| Married couple, no children | 65.2% | 75.9% | 42.9% |
| Non Family Households | 52 | 128 | 43,255,233 |
| Single householder, w/children | 24.6% | 3.6% | 15.8% |
| Single householder, no children | 7.2% | 15.4% | 10.8% |