The patron of Oppido Mamertina is Mary Most Holy Annunciated, celebrated on 25 March and again on 15 August.
The town's calendar of feasts also includes Saint Joseph on 19 March and Saint Rita of Cascia on 22 May; in the hamlet of Tresilico, Our Lady of Grace is celebrated on 2 July, while in the hamlet of Piminoro the Divine Shepherdess is celebrated on the second Sunday of July. The town also holds the Church of San Giuseppe and the Diocesan Museum.