King William County's 2026 population is estimated at 19,955, reflecting a 1.72% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). King William County is the 82nd largest county in Virginia. The 2010 population was 15,999 and has grown 24.73% since 2010.
Overall: 40.9 years
Female: 41.8 years
Male: 38.3 years
There are 14,369 adults, (3,129 of whom are seniors) in King William County.
Female: 9,487 (51%)
Male: 9,106 (49%)
The racial composition of King William County includes 77.56% White, 15.03% Black or African American, and smaller percentages for Native American, other race, Asian, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 14,420 | 77.56% |
| Black or African American | 2,795 | 15.03% |
| Two or more races | 893 | 4.8% |
| Native American | 208 | 1.12% |
| Other race | 151 | 0.81% |
| Asian | 116 | 0.62% |
| Native Hawaiian or Pacific Islander | 10 | 0.05% |
King William County 's average per capita income is $55,165. Household income levels show a median of $86,056. The poverty rate stands at 5.86%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $116,652 | - |
| Families | $98,408 | $112,183 |
| Households | $86,056 | $99,161 |
| Non Families | $43,750 | $55,189 |
Average Income
Median Household Income
Poverty Rate