| | Dallastown, PA | Red Lion, PA | United States |
| Population | 4,147 | 6,478 | 329,725,481 |
| Female Population | 53.1% | 51.8% | 50.5% |
| Male Population | 46.9% | 48.2% | 49.5% |
| Median Age | 39.5 | 36.9 | 38.4 |
| space3 | | | |
| Population - 2010 | 3,915 | 6,359 | 309,327,143 |
| Population - 2000 | 4,087 | 6,149 | 285,036,114 |
| Population - 1990 | 3,974 | 6,130 | 251,960,433 |
| Pop. 2000 to Now | -5.3% | 2.6% | 15.6% |
| Pop. 1990 to Now | -2.6% | 2.9% | 30.8% |
| space4 | | | |
| Population Density | 5,330.3 | 4,933.7 | 93.4 |
| Land Area | 0.8 | 1.3 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Dallastown, PA | Red Lion, PA | United States |
| Age 0 to 4 | 9.9% | 5.9% | 5.9% |
| Age 5 to 9 | 5.5% | 5.9% | 6.1% |
| Age 10 to 14 | 5.5% | 6.5% | 6.6% |
| Age 15 to 17 | 1.3% | 1.0% | 3.9% |
| Age 18 to 20 | 1.1% | 2.9% | 4.0% |
| Age 21 to 24 | 7.9% | 3.8% | 5.2% |
| Age 25 to 34 | 11.4% | 19.9% | 13.8% |
| Age 35 to 44 | 14.5% | 12.0% | 12.9% |
| Age 45 to 54 | 15.3% | 10.8% | 12.6% |
| Age 55 to 59 | 8.5% | 10.1% | 6.7% |
| Age 60 to 64 | 7.4% | 6.1% | 6.3% |
| Age 65 to 74 | 7.1% | 6.8% | 9.6% |
| Age 75 to 84 | 2.0% | 4.6% | 4.5% |
| Age 85 and over | 2.6% | 3.6% | 1.9% |
| space1 | | | |
| Race | | | |
| | Dallastown, PA | Red Lion, PA | United States |
| White | 93.2% | 87.6% | 59.4% |
| Black | 1.4% | 2.7% | 12.2% |
| Asian | 0.0% | 2.5% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 1.3% | 0.0% | 0.4% |
| Two or More Races | 2.3% | 4.0% | 3.2% |
| Hispanic | 1.9% | 3.1% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Dallastown, PA | Red Lion, PA | United States |
| Married Population | 49.7% | 39.0% | 49.8% |
| Currently Married | 47.5% | 38.0% | 48.0% |
| Married but Separated | 2.2% | 1.0% | 1.8% |
| Single Population | 50.3% | 61.0% | 50.2% |
| Never Married | 25.7% | 34.9% | 33.8% |
| Divorced | 20.3% | 16.7% | 10.8% |
| Widowed | 4.3% | 9.5% | 5.6% |
| space5 | | | |
| Household Size | 2.37 | 2.32 | 2.60 |
| Households | 1,738 | 2,787 | 124,010,992 |
| Family Households | 1,115 | 1,543 | 80,755,759 |
| Married couple, w/children | 37.2% | 23.6% | 30.5% |
| Married couple, no children | 33.5% | 35.0% | 42.9% |
| Non Family Households | 623 | 1,244 | 43,255,233 |
| Single householder, w/children | 19.2% | 22.7% | 15.8% |
| Single householder, no children | 10.0% | 18.7% | 10.8% |