| | Kilmarnock, VA | Lexington Park, MD | United States |
| Population | 1,424 | 12,681 | 329,725,481 |
| Female Population | 61.2% | 50.4% | 50.5% |
| Male Population | 38.8% | 49.6% | 49.5% |
| Median Age | 56 | 31.3 | 38.4 |
| space3 | | | |
| Population - 2010 | 1,487 | 10,882 | 309,327,143 |
| Population - 2000 | 1,244 | 11,021 | 285,036,114 |
| Population - 1990 | 1,109 | 9,943 | 251,960,433 |
| Pop. 2000 to Now | 12.5% | 11.8% | 15.6% |
| Pop. 1990 to Now | 26.2% | 23.9% | 30.8% |
| space4 | | | |
| Population Density | 417.8 | 2,255.6 | 93.4 |
| Land Area | 3.4 | 5.6 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Kilmarnock, VA | Lexington Park, MD | United States |
| Age 0 to 4 | 8.8% | 7.8% | 5.9% |
| Age 5 to 9 | 3.4% | 6.4% | 6.1% |
| Age 10 to 14 | 1.1% | 4.7% | 6.6% |
| Age 15 to 17 | 2.8% | 5.8% | 3.9% |
| Age 18 to 20 | 1.7% | 4.0% | 4.0% |
| Age 21 to 24 | 2.9% | 6.9% | 5.2% |
| Age 25 to 34 | 13.0% | 21.1% | 13.8% |
| Age 35 to 44 | 8.1% | 15.5% | 12.9% |
| Age 45 to 54 | 7.0% | 10.8% | 12.6% |
| Age 55 to 59 | 8.1% | 5.7% | 6.7% |
| Age 60 to 64 | 7.5% | 5.2% | 6.3% |
| Age 65 to 74 | 18.3% | 4.0% | 9.6% |
| Age 75 to 84 | 13.6% | 1.1% | 4.5% |
| Age 85 and over | 3.6% | 0.9% | 1.9% |
| space1 | | | |
| Race | | | |
| | Kilmarnock, VA | Lexington Park, MD | United States |
| White | 69.5% | 50.5% | 59.4% |
| Black | 25.4% | 29.9% | 12.2% |
| Asian | 3.3% | 5.3% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.5% | 0.4% |
| Two or More Races | 1.2% | 6.6% | 3.2% |
| Hispanic | 0.6% | 7.1% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Kilmarnock, VA | Lexington Park, MD | United States |
| Married Population | 36.6% | 37.4% | 49.8% |
| Currently Married | 35.0% | 36.2% | 48.0% |
| Married but Separated | 1.6% | 1.2% | 1.8% |
| Single Population | 63.4% | 62.6% | 50.2% |
| Never Married | 30.9% | 50.0% | 33.8% |
| Divorced | 18.0% | 9.9% | 10.8% |
| Widowed | 14.5% | 2.7% | 5.6% |
| space5 | | | |
| Household Size | 1.91 | 2.35 | 2.60 |
| Households | 687 | 5,358 | 124,010,992 |
| Family Households | 307 | 3,244 | 80,755,759 |
| Married couple, w/children | 8.8% | 31.8% | 30.5% |
| Married couple, no children | 57.0% | 20.5% | 42.9% |
| Non Family Households | 380 | 2,114 | 43,255,233 |
| Single householder, w/children | 26.7% | 37.0% | 15.8% |
| Single householder, no children | 7.5% | 10.7% | 10.8% |