The patron saint of Sermoneta is Saint Joseph, celebrated on 19 March in the Church of San Giuseppe.
The second Sunday of January holds the Polenta Festival, a local dish; 18 March the Festa dei fauni; in August the Sermoneta in Folklore International Festival; in September the age-old Fiera di San Michele. The town also commemorates a historical reenactment of the Battle of Lepanto, in which Duke Onorato IV Caetani took part. The town also holds the Abbey of Valvisciolo and the Caetani Castle.
