The Toce is a river in Piedmont, Italy, which stretches the length of the Val d'Ossola from the Swiss border to Lake Maggiore into which it debouches near Fondotoce in the commune of Verbania. The river is 83.6 kilometres (51.9 mi) long and is formed in the upper Val Formazza by the confluence of a number of torrents in the plain of Riale.