Allison
- County:
- Brown County
- County Seat:
- No
- Area (mi²):
- 35.888
- State:
- South Dakota
Allison is located in Brown County, South Dakota. Allison has a 2025 population of 23. Allison is currently declining at a rate of -4.17% annually and its population has decreased by -11.54% since the most recent census, which recorded a population of 26 in 2020.
The median age in Allison is 15.3 years: 13 years for males, and 17.3 years for females.