| | Fairfield, PA | Fairview, PA | United States |
| Population | 690 | 2,926 | 329,725,481 |
| Female Population | 49.3% | 52.5% | 50.5% |
| Male Population | 50.7% | 47.5% | 49.5% |
| Median Age | 39.1 | 38.2 | 38.4 |
| space3 | | | |
| Population - 2010 | 509 | 2,921 | 309,327,143 |
| Population - 2000 | 486 | 2,208 | 285,036,114 |
| Population - 1990 | 524 | 1,988 | 251,960,433 |
| Pop. 2000 to Now | 6.2% | 35.7% | 15.6% |
| Pop. 1990 to Now | -1.5% | 50.7% | 30.8% |
| space4 | | | |
| Population Density | 1,025.3 | 831.7 | 93.4 |
| Land Area | 0.7 | 3.5 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Fairfield, PA | Fairview, PA | United States |
| Age 0 to 4 | 4.8% | 6.9% | 5.9% |
| Age 5 to 9 | 2.9% | 5.1% | 6.1% |
| Age 10 to 14 | 8.7% | 8.3% | 6.6% |
| Age 15 to 17 | 10.0% | 2.0% | 3.9% |
| Age 18 to 20 | 4.9% | 3.2% | 4.0% |
| Age 21 to 24 | 1.9% | 1.4% | 5.2% |
| Age 25 to 34 | 8.1% | 14.0% | 13.8% |
| Age 35 to 44 | 12.6% | 19.2% | 12.9% |
| Age 45 to 54 | 11.7% | 2.2% | 12.6% |
| Age 55 to 59 | 7.5% | 3.3% | 6.7% |
| Age 60 to 64 | 3.8% | 4.2% | 6.3% |
| Age 65 to 74 | 11.0% | 17.6% | 9.6% |
| Age 75 to 84 | 7.1% | 8.8% | 4.5% |
| Age 85 and over | 4.9% | 3.9% | 1.9% |
| space1 | | | |
| Race | | | |
| | Fairfield, PA | Fairview, PA | United States |
| White | 95.2% | 93.0% | 59.4% |
| Black | 0.0% | 1.4% | 12.2% |
| Asian | 0.0% | 0.0% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 3.5% | 0.0% | 3.2% |
| Hispanic | 1.3% | 5.6% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Fairfield, PA | Fairview, PA | United States |
| Married Population | 61.9% | 62.1% | 49.8% |
| Currently Married | 60.3% | 62.1% | 48.0% |
| Married but Separated | 1.6% | 0.0% | 1.8% |
| Single Population | 38.1% | 37.9% | 50.2% |
| Never Married | 26.3% | 18.2% | 33.8% |
| Divorced | 7.1% | 6.7% | 10.8% |
| Widowed | 4.7% | 12.9% | 5.6% |
| space5 | | | |
| Household Size | 2.74 | 2.74 | 2.60 |
| Households | 252 | 959 | 124,010,992 |
| Family Households | 186 | 778 | 80,755,759 |
| Married couple, w/children | 40.9% | 36.2% | 30.5% |
| Married couple, no children | 46.2% | 51.0% | 42.9% |
| Non Family Households | 66 | 181 | 43,255,233 |
| Single householder, w/children | 9.1% | 10.5% | 15.8% |
| Single householder, no children | 3.8% | 2.2% | 10.8% |