Catechism of the Catholic Church §1457 — excerpt
According to the Church's command, "after having attained the age of discretion, each of the faithful is bound by an obligation faithfully to confess serious sins at least once a year."
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: CIC, Can. 989 · Council of Trent (1551): DS 1683 · DS 1708 · Council of Trent (1551): DS 1647 · 1661 · CIC, can. 916 · CCEO, can. 711 · CIC, can. 914