| Official Name: | Seneca, New Mexico |
| Pushpin Map: | New Mexico |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | New Mexico |
| Subdivision Type2: | County |
| Subdivision Name2: | Union |
| Timezone: | Mountain (MST) |
| Utc Offset: | -7 |
| Timezone Dst: | MDT |
| Utc Offset Dst: | -6 |
| Elevation Ft: | 4990 |
| Coordinates: | 36.6283°N -103.1267°W |
| Area Code: | 575 |
| Blank Name: | GNIS feature ID |
| Blank Info: | 910940 |
Seneca is an unincorporated community in Union County, New Mexico, United States. Seneca is located on New Mexico State Road 406, 12.6miles north-northeast of Clayton. Originally known as Cienaga, the name was corrupted by Anglophone settlers after the Civil War. The first postmaster was Flora Blackwell.[1]