San Callisto (English: Saint Callixtus, Latin: S. Calixti) is a Roman Catholic titular church in Rome, Italy, built over the site of Pope Callixtus I's martyrdom (c. AD 222).

The original building dates from the time of Pope Gregory III (r. 731–741), who ordered the building of a church on the site. The church has been rebuilt twice since, first in the twelfth century, and the current church restored in 1610 by Orazio Torriani for the Benedictine monks of Montecassino.^[1]

In January 2017, in response to Pope Francis's call for an increase in aid to the homeless, especially during the cold winter weather, the Community of Sant'Egidio opened San Callisto as an overnight shelter, with a hot meal available at a nearby cafeteria.^[2]

Established in 1517, the Titulus San Calixti is currently held by Willem Jacobus Cardinal Eijk.^[3]

The seventeenth-century facade carried the coat of arms of Paul V. The altarpiece, by, Avanzino Nucci, depicts the "Glora di San Callisto". The church has a single aisle with a chapel on either side. Within the chapel to the right, two angels attributed to Gian Lorenzo Bernini support a painting by Pier Leone Ghezzi. The chapel on the left contains the well where Callistus I, later venerated as a saint, was martyred.^[1]