| Fontaine-sur-Aÿ | |
| Commune Status: | Commune |
| Arrondissement: | Épernay |
| Canton: | Épernay-1 |
| Insee: | 51256 |
| Postal Code: | 51160 |
| Mayor: | Alain-Louis Gourdy[1] |
| Term: | 2022 - 2026 |
| Intercommunality: | Grande Vallée de la Marne |
| Coordinates: | 49.0828°N 4.0733°W |
| Elevation M: | 90 |
| Area Km2: | 7.72 |
Fontaine-sur-Ay (pronounced as /fr/, literally Fontaine on Ay; also Fontaine-sur-Aÿ) is a commune in the Marne department in north-eastern France.This village lies in the Champagne region, known for its sparkling wines. Fontaine-sur-Ay spans an area of 7.72 km², with altitudes ranging between 87 and 271 meters above sea level. Its postal code is 51160.
Two rivers, the Germaine and the Livre, flow through the area, meeting near the village center. [2]