| Official Name: | Hadley, New York |
| Settlement Type: | Census-designated place |
| Pushpin Map: | New York#USA |
| Pushpin Label: | Hadley |
| Coordinates: | 43.3169°N -73.8481°W |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | New York |
| Subdivision Type2: | County |
| Subdivision Name2: | Saratoga |
| Subdivision Type3: | Town |
| Subdivision Name3: | Hadley |
| Area Footnotes: | [1] |
| Area Total Sq Mi: | 1.67 |
| Area Land Sq Mi: | 1.45 |
| Area Water Sq Mi: | 0.21 |
| Area Total Km2: | 4.31 |
| Area Land Km2: | 3.77 |
| Area Water Km2: | 0.55 |
| Population As Of: | 2020 |
| Population Density Km2: | 298.40 |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation Ft: | 630 |
| Postal Code Type: | ZIP Code |
| Postal Code: | 12835 |
| Area Code: | 518/838 |
| Blank Name: | FIPS code |
| Blank Info: | 36-31258 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 2584264 |
| Population Total: | 1124 |
| Unit Pref: | Imperial |
| Population Density Sq Mi: | 773.04 |
Hadley is the primary hamlet and a census-designated place (CDP) within the town of Hadley, Saratoga County, New York, United States. As of the 2010 census, the population was 1,009, out of 1,971 residents in the entire town of Hadley. Before that, the community was part of the Lake Luzerne-Hadley census-designated place.
Hadley CDP is in northern Saratoga County, in the southeastern part of its town. It is bordered to the east by the Hudson River, across which is the town of Lake Luzerne in Warren County. The Sacandaga River forms the southern edge of Hadley, joining the Hudson at the community's southeastern corner.
By road, Hadley is 5miles north of Corinth, west of Glens Falls, and north of Saratoga Springs.