| | Richfield, UT | Green River, UT | United States |
| Population | 8,086 | 800 | 329,725,481 |
| Female Population | 50.4% | 52.8% | 50.5% |
| Male Population | 49.6% | 47.3% | 49.5% |
| Median Age | 31.9 | 40.3 | 38.4 |
| space3 | | | |
| Population - 2010 | 7,563 | 1,031 | 309,327,143 |
| Population - 2000 | 6,847 | 973 | 285,036,114 |
| Population - 1990 | 5,593 | 866 | 251,960,433 |
| Pop. 2000 to Now | 15.5% | -1.6% | 15.6% |
| Pop. 1990 to Now | 41.4% | 10.5% | 30.8% |
| space4 | | | |
| Population Density | 1,425.1 | 29.5 | 93.4 |
| Land Area | 5.7 | 27.1 | 3,531,905.4 |
| Water Area | 0.0 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Richfield, UT | Green River, UT | United States |
| Age 0 to 4 | 8.3% | 7.4% | 5.9% |
| Age 5 to 9 | 10.2% | 7.5% | 6.1% |
| Age 10 to 14 | 10.2% | 4.9% | 6.6% |
| Age 15 to 17 | 5.8% | 5.9% | 3.9% |
| Age 18 to 20 | 4.2% | 3.4% | 4.0% |
| Age 21 to 24 | 3.6% | 1.4% | 5.2% |
| Age 25 to 34 | 11.5% | 11.3% | 13.8% |
| Age 35 to 44 | 16.0% | 18.1% | 12.9% |
| Age 45 to 54 | 9.0% | 15.8% | 12.6% |
| Age 55 to 59 | 5.0% | 5.3% | 6.7% |
| Age 60 to 64 | 5.0% | 4.6% | 6.3% |
| Age 65 to 74 | 6.5% | 9.3% | 9.6% |
| Age 75 to 84 | 3.2% | 4.6% | 4.5% |
| Age 85 and over | 1.6% | 0.8% | 1.9% |
| space1 | | | |
| Race | | | |
| | Richfield, UT | Green River, UT | United States |
| White | 91.7% | 67.0% | 59.4% |
| Black | 1.2% | 0.0% | 12.2% |
| Asian | 0.2% | 0.0% | 5.6% |
| Native American | 0.9% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.1% | 0.0% | 0.4% |
| Two or More Races | 0.7% | 0.0% | 3.2% |
| Hispanic | 5.2% | 33.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Richfield, UT | Green River, UT | United States |
| Married Population | 56.2% | 58.7% | 49.8% |
| Currently Married | 55.2% | 57.9% | 48.0% |
| Married but Separated | 1.0% | 0.8% | 1.8% |
| Single Population | 43.8% | 41.3% | 50.2% |
| Never Married | 28.6% | 24.9% | 33.8% |
| Divorced | 9.6% | 7.2% | 10.8% |
| Widowed | 5.6% | 9.2% | 5.6% |
| space5 | | | |
| Household Size | 3.08 | 2.55 | 2.60 |
| Households | 2,547 | 314 | 124,010,992 |
| Family Households | 1,809 | 215 | 80,755,759 |
| Married couple, w/children | 49.1% | 35.8% | 30.5% |
| Married couple, no children | 35.1% | 43.7% | 42.9% |
| Non Family Households | 738 | 99 | 43,255,233 |
| Single householder, w/children | 14.3% | 14.0% | 15.8% |
| Single householder, no children | 1.5% | 6.5% | 10.8% |