Blenheim
- County:
- Marlboro County
- County Seat:
- No
- Area (mi²):
- 0.653
- State:
- South Carolina
Blenheim is a town located in Marlboro County, South Carolina. Blenheim has a 2026 population of 107. Blenheim is currently declining at a rate of -2.73% annually and its population has decreased by -5.31% since the most recent census, which recorded a population of 113 in 2020.
The median household income in Blenheim is $49,167 with a poverty rate of 21.52%. The median age in Blenheim is 40.9 years: 45.3 years for males, and 40.6 years for females. For every 100 females there are 78.3 males.