Frederick
- County:
- Brown County
- County Seat:
- No
- Area (mi²):
- 1.354
- State:
- South Dakota
Frederick is a town located in Brown County, South Dakota. Frederick has a 2026 population of 209. Frederick is currently declining at a rate of 0% annually and its population has decreased by -2.34% since the most recent census, which recorded a population of 214 in 2020.
The median household income in Frederick is $76,667 with a poverty rate of 11.25%. The median age in Frederick is 52.8 years: 50.9 years for males, and 55 years for females. For every 100 females there are 105.1 males.