| | Parmelee, SD | Mission, SD | United States |
| Population | 528 | 1,216 | 329,725,481 |
| Female Population | 40.5% | 51.4% | 50.5% |
| Male Population | 59.5% | 48.6% | 49.5% |
| Median Age | 20.6 | 21.4 | 38.4 |
| space3 | | | |
| Population - 2010 | 747 | 1,185 | 309,327,143 |
| Population - 2000 | 650 | 904 | 285,036,114 |
| Population - 1990 | 618 | 730 | 251,960,433 |
| Pop. 2000 to Now | 27.7% | 40.4% | 15.6% |
| Pop. 1990 to Now | 34.3% | 73.8% | 30.8% |
| space4 | | | |
| Population Density | 92.4 | 2,071.6 | 93.4 |
| Land Area | 5.7 | 0.6 | 3,531,905.4 |
| Water Area | 0.1 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Parmelee, SD | Mission, SD | United States |
| Age 0 to 4 | 6.8% | 16.7% | 5.9% |
| Age 5 to 9 | 17.4% | 13.3% | 6.1% |
| Age 10 to 14 | 15.0% | 10.7% | 6.6% |
| Age 15 to 17 | 5.7% | 3.5% | 3.9% |
| Age 18 to 20 | 7.4% | 5.3% | 4.0% |
| Age 21 to 24 | 7.0% | 2.8% | 5.2% |
| Age 25 to 34 | 13.4% | 18.7% | 13.8% |
| Age 35 to 44 | 5.3% | 8.6% | 12.9% |
| Age 45 to 54 | 11.0% | 8.1% | 12.6% |
| Age 55 to 59 | 7.4% | 2.8% | 6.7% |
| Age 60 to 64 | 3.6% | 2.9% | 6.3% |
| Age 65 to 74 | 0.0% | 5.7% | 9.6% |
| Age 75 to 84 | 0.0% | 0.7% | 4.5% |
| Age 85 and over | 0.0% | 0.3% | 1.9% |
| space1 | | | |
| Race | | | |
| | Parmelee, SD | Mission, SD | United States |
| White | 0.0% | 11.6% | 59.4% |
| Black | 0.0% | 0.0% | 12.2% |
| Asian | 0.0% | 1.1% | 5.6% |
| Native American | 100.0% | 78.9% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 0.0% | 4.7% | 3.2% |
| Hispanic | 0.0% | 3.7% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Parmelee, SD | Mission, SD | United States |
| Married Population | 13.1% | 25.2% | 49.8% |
| Currently Married | 13.1% | 22.7% | 48.0% |
| Married but Separated | 0.0% | 2.5% | 1.8% |
| Single Population | 86.9% | 74.8% | 50.2% |
| Never Married | 74.1% | 61.7% | 33.8% |
| Divorced | 3.1% | 9.7% | 10.8% |
| Widowed | 9.7% | 3.3% | 5.6% |
| space5 | | | |
| Household Size | 5.33 | 3.39 | 2.60 |
| Households | 99 | 359 | 124,010,992 |
| Family Households | 74 | 238 | 80,755,759 |
| Married couple, w/children | 14.9% | 24.4% | 30.5% |
| Married couple, no children | 17.6% | 10.9% | 42.9% |
| Non Family Households | 25 | 121 | 43,255,233 |
| Single householder, w/children | 52.7% | 51.7% | 15.8% |
| Single householder, no children | 14.9% | 13.0% | 10.8% |