New Effington
- County:
- Roberts County
- County Seat:
- No
- Area (mi²):
- 0.261
- State:
- South Dakota
New Effington is a town located in Roberts County, South Dakota. New Effington has a 2026 population of 228. New Effington is currently growing at a rate of 0.88% annually but its population has decreased by -2.15% since the most recent census, which recorded a population of 233 in 2020.