| Cosne-d'Allier | |
| Commune Status: | Commune |
| Image Coat Of Arms: | Blason de la ville de Cosne-d'Allier (03).svg |
| Arrondissement: | Montluçon |
| Canton: | Huriel |
| Insee: | 03084 |
| Postal Code: | 03430 |
| Mayor: | Marie Carré[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Commentry Montmarault Néris Communauté |
| Coordinates: | 46.4761°N 2.8322°W |
| Elevation M: | 230 |
| Elevation Min M: | 217 |
| Elevation Max M: | 312 |
| Area Km2: | 25.29 |
Cosne-d'Allier (in French pronounced as /kon dalje/; Occitan (post 1500);: Còse) is a commune in the Allier department in central France.