Sidney
- County:
- Delaware County
- County Seat:
- No
- Area (mi²):
- 2.38
- State:
- New York
Sidney is a village located in Delaware County, New York. Sidney has a 2026 population of 3,613. Sidney is currently declining at a rate of -1.01% annually and its population has decreased by -2.48% since the most recent census, which recorded a population of 3,705 in 2020.