| | North Eagle Butte, SD | Isabel, SD | United States |
| Population | 1,731 | 186 | 329,725,481 |
| Female Population | 51.6% | 53.2% | 50.5% |
| Male Population | 48.4% | 46.8% | 49.5% |
| Median Age | 22.6 | 38.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,902 | 136 | 309,327,143 |
| Population - 2000 | 2,163 | 239 | 285,036,114 |
| Population - 1990 | 1,423 | 319 | 251,960,433 |
| Pop. 2000 to Now | -1.2% | -37.2% | 15.6% |
| Pop. 1990 to Now | 50.3% | -53.0% | 30.8% |
| space4 | | | |
| Population Density | 190.0 | 205.5 | 93.4 |
| Land Area | 9.1 | 0.9 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | North Eagle Butte, SD | Isabel, SD | United States |
| Age 0 to 4 | 13.4% | 1.1% | 5.9% |
| Age 5 to 9 | 14.0% | 5.4% | 6.1% |
| Age 10 to 14 | 8.6% | 10.8% | 6.6% |
| Age 15 to 17 | 4.9% | 4.8% | 3.9% |
| Age 18 to 20 | 7.4% | 0.5% | 4.0% |
| Age 21 to 24 | 4.2% | 7.5% | 5.2% |
| Age 25 to 34 | 9.8% | 7.0% | 13.8% |
| Age 35 to 44 | 12.2% | 21.0% | 12.9% |
| Age 45 to 54 | 8.6% | 8.1% | 12.6% |
| Age 55 to 59 | 3.6% | 10.8% | 6.7% |
| Age 60 to 64 | 6.4% | 9.1% | 6.3% |
| Age 65 to 74 | 4.3% | 9.1% | 9.6% |
| Age 75 to 84 | 2.5% | 2.7% | 4.5% |
| Age 85 and over | 0.1% | 2.2% | 1.9% |
| space1 | | | |
| Race | | | |
| | North Eagle Butte, SD | Isabel, SD | United States |
| White | 0.7% | 71.0% | 59.4% |
| Black | 0.0% | 1.1% | 12.2% |
| Asian | 0.0% | 0.0% | 5.6% |
| Native American | 96.1% | 26.9% | 0.6% |
| Hawaiian, Pacific Islander | 0.9% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 0.0% | 1.1% | 3.2% |
| Hispanic | 2.3% | 0.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | North Eagle Butte, SD | Isabel, SD | United States |
| Married Population | 23.6% | 39.6% | 49.8% |
| Currently Married | 22.7% | 39.6% | 48.0% |
| Married but Separated | 1.0% | 0.0% | 1.8% |
| Single Population | 76.4% | 60.4% | 50.2% |
| Never Married | 49.5% | 37.0% | 33.8% |
| Divorced | 20.1% | 18.2% | 10.8% |
| Widowed | 6.7% | 5.2% | 5.6% |
| space5 | | | |
| Household Size | 3.93 | 2.07 | 2.60 |
| Households | 439 | 90 | 124,010,992 |
| Family Households | 296 | 55 | 80,755,759 |
| Married couple, w/children | 27.0% | 20.0% | 30.5% |
| Married couple, no children | 8.1% | 43.6% | 42.9% |
| Non Family Households | 143 | 35 | 43,255,233 |
| Single householder, w/children | 53.4% | 23.6% | 15.8% |
| Single householder, no children | 11.5% | 12.7% | 10.8% |