| | Lower Southampton, PA | Horsham, PA | United States |
| Population | 20,410 | 15,384 | 329,725,481 |
| Female Population | 53.0% | 49.0% | 50.5% |
| Male Population | 47.0% | 51.0% | 49.5% |
| Median Age | 45.5 | 36.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 18,919 | 14,413 | 309,327,143 |
| Population - 2000 | 19,276 | 14,779 | 285,036,114 |
| Population - 1990 | 19,860 | 15,051 | 251,960,433 |
| Pop. 2000 to Now | -0.7% | 0.5% | 15.6% |
| Pop. 1990 to Now | -3.6% | -1.3% | 30.8% |
| space4 | | | |
| Population Density | 3,058.1 | 2,812.4 | 93.4 |
| Land Area | 6.7 | 5.5 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Lower Southampton, PA | Horsham, PA | United States |
| Age 0 to 4 | 4.7% | 4.6% | 5.9% |
| Age 5 to 9 | 4.6% | 7.8% | 6.1% |
| Age 10 to 14 | 5.2% | 8.9% | 6.6% |
| Age 15 to 17 | 3.3% | 4.2% | 3.9% |
| Age 18 to 20 | 2.5% | 2.2% | 4.0% |
| Age 21 to 24 | 4.9% | 5.0% | 5.2% |
| Age 25 to 34 | 12.0% | 16.1% | 13.8% |
| Age 35 to 44 | 12.4% | 12.2% | 12.9% |
| Age 45 to 54 | 13.9% | 9.0% | 12.6% |
| Age 55 to 59 | 6.8% | 5.3% | 6.7% |
| Age 60 to 64 | 9.8% | 7.5% | 6.3% |
| Age 65 to 74 | 13.4% | 11.9% | 9.6% |
| Age 75 to 84 | 5.1% | 3.8% | 4.5% |
| Age 85 and over | 1.6% | 1.5% | 1.9% |
| space1 | | | |
| Race | | | |
| | Lower Southampton, PA | Horsham, PA | United States |
| White | 87.6% | 71.2% | 59.4% |
| Black | 2.2% | 3.1% | 12.2% |
| Asian | 4.2% | 7.7% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 3.4% | 0.4% |
| Two or More Races | 3.8% | 2.4% | 3.2% |
| Hispanic | 2.2% | 12.2% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Lower Southampton, PA | Horsham, PA | United States |
| Married Population | 57.0% | 55.6% | 49.8% |
| Currently Married | 55.8% | 53.1% | 48.0% |
| Married but Separated | 1.2% | 2.5% | 1.8% |
| Single Population | 43.0% | 44.4% | 50.2% |
| Never Married | 28.1% | 31.7% | 33.8% |
| Divorced | 7.8% | 7.8% | 10.8% |
| Widowed | 7.1% | 4.8% | 5.6% |
| space5 | | | |
| Household Size | 2.59 | 2.69 | 2.60 |
| Households | 7,880 | 5,666 | 124,010,992 |
| Family Households | 5,794 | 3,889 | 80,755,759 |
| Married couple, w/children | 29.3% | 36.2% | 30.5% |
| Married couple, no children | 52.4% | 37.5% | 42.9% |
| Non Family Households | 2,086 | 1,777 | 43,255,233 |
| Single householder, w/children | 9.8% | 17.5% | 15.8% |
| Single householder, no children | 8.6% | 8.7% | 10.8% |