The patron saint of Corsico is Our Lady of the Belt, celebrated on 7 December, the feast of Saint Ambrose according to the Ambrosian liturgical calendar followed by the diocese of Milan.
The town's main places of worship are the parish church of Santi Pietro e Paolo and the parish church of Sant'Antonio da Padova. Corsico experienced a moment of great popular participation on 25 April 1945, when the uprising ended the German occupation; the town celebrated four days later, on 29 April, when Allied forces entered the Milan area.
