The Lignon du Forez (French pronunciation: [liɲɔ̃ dy fɔʁɛ], literally Lignon of the Forez; also called Lignon de Chalmazel, literally Lignon of Chalmazel) is a 58.9 km (36.6 mi) long river in the Loire department, east-central France. Its source is near Chalmazel. It flows generally east. It is a left tributary of the Loire into which it flows near Feurs.

Communes along its course

This list is ordered from source to mouth:

Chalmazel, Jeansagnière, Sauvain, Saint-Bonnet-le-Courreau, Saint-Georges-en-Couzan, Sail-sous-Couzan, Saint-Sixte, Leigneux, Boën, Trelins, Marcoux, Sainte-Agathe-la-Bouteresse, Montverdun, Saint-Étienne-le-Molard, Poncins, Cleppé, Feurs