| Bay | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason ville fr Bay (Haute-Saône).svg |
| Coordinates: | 47.2897°N 5.7208°W |
| Insee: | 70057 |
| Postal Code: | 70150 |
| Arrondissement: | Vesoul |
| Canton: | Marnay |
| Elevation Min M: | 203 |
| Elevation Max M: | 303 |
| Area Km2: | 4.87 |
Bay is a commune in the Haute-Saône department in the region of Bourgogne-Franche-Comté in eastern France.