
Alcester
- County:
- Union County
- County Seat:
- No
- Area (mi²):
- 0.734
- State:
- South Dakota
Alcester is a city located in Union County, South Dakota. Alcester has a 2025 population of 751. Alcester is currently declining at a rate of -1.96% annually and its population has decreased by -8.97% since the most recent census, which recorded a population of 825 in 2020.
The average household income in Alcester is $67,612 with a poverty rate of 12.11%. The median age in Alcester is 42.9 years: 40 years for males, and 50.3 years for females.