| | Arlington, OR | The Dalles, OR | United States |
| Population | 538 | 15,942 | 329,725,481 |
| Female Population | 51.5% | 52.5% | 50.5% |
| Male Population | 48.5% | 47.6% | 49.5% |
| Median Age | 40.6 | 37.7 | 38.4 |
| space3 | | | |
| Population - 2010 | 591 | 14,983 | 309,327,143 |
| Population - 2000 | 524 | 13,853 | 285,036,114 |
| Population - 1990 | 425 | 12,726 | 251,960,433 |
| Pop. 2000 to Now | 19.5% | 12.5% | 15.6% |
| Pop. 1990 to Now | 47.3% | 22.4% | 30.8% |
| space4 | | | |
| Population Density | 210.8 | 2,394.1 | 93.4 |
| Land Area | 2.6 | 6.7 | 3,531,905.4 |
| Water Area | 0.6 | 0.3 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Arlington, OR | The Dalles, OR | United States |
| Age 0 to 4 | 2.2% | 6.3% | 5.9% |
| Age 5 to 9 | 8.7% | 5.7% | 6.1% |
| Age 10 to 14 | 7.1% | 8.6% | 6.6% |
| Age 15 to 17 | 4.8% | 3.8% | 3.9% |
| Age 18 to 20 | 0.0% | 3.4% | 4.0% |
| Age 21 to 24 | 11.9% | 4.6% | 5.2% |
| Age 25 to 34 | 11.5% | 13.3% | 13.8% |
| Age 35 to 44 | 11.3% | 13.4% | 12.9% |
| Age 45 to 54 | 11.5% | 10.1% | 12.6% |
| Age 55 to 59 | 2.8% | 5.1% | 6.7% |
| Age 60 to 64 | 11.7% | 6.8% | 6.3% |
| Age 65 to 74 | 5.2% | 10.3% | 9.6% |
| Age 75 to 84 | 3.2% | 5.2% | 4.5% |
| Age 85 and over | 8.0% | 3.4% | 1.9% |
| space1 | | | |
| Race | | | |
| | Arlington, OR | The Dalles, OR | United States |
| White | 88.7% | 75.1% | 59.4% |
| Black | 0.0% | 0.3% | 12.2% |
| Asian | 0.9% | 0.9% | 5.6% |
| Native American | 0.6% | 0.7% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.3% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 2.4% | 3.7% | 3.2% |
| Hispanic | 7.4% | 19.0% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Arlington, OR | The Dalles, OR | United States |
| Married Population | 34.0% | 47.0% | 49.8% |
| Currently Married | 34.0% | 45.5% | 48.0% |
| Married but Separated | 0.0% | 1.5% | 1.8% |
| Single Population | 66.0% | 53.0% | 50.2% |
| Never Married | 34.5% | 31.1% | 33.8% |
| Divorced | 19.0% | 12.9% | 10.8% |
| Widowed | 12.5% | 8.9% | 5.6% |
| space5 | | | |
| Household Size | 2.38 | 2.51 | 2.60 |
| Households | 226 | 6,189 | 124,010,992 |
| Family Households | 130 | 3,796 | 80,755,759 |
| Married couple, w/children | 17.7% | 31.6% | 30.5% |
| Married couple, no children | 36.9% | 39.4% | 42.9% |
| Non Family Households | 96 | 2,393 | 43,255,233 |
| Single householder, w/children | 20.0% | 16.1% | 15.8% |
| Single householder, no children | 25.4% | 12.9% | 10.8% |