Encyclopædia Britannica: Matthias
- Brief entry on the disciple chosen to replace Judas Iscariot. In the 11th edition (1911).
- http://encyclopedia.jrank.org/MAR_MEC/MATTHIAS.html

Matthias of Jerusalem, Apostle
- Concise biography.
- http://www.saintpatrickdc.org/ss/0514.htm#matt

Catholic Online: Saint Matthias, Apostle
- Short devotional centered on his election as an Apostle.
- http://www.catholic.org/saints/saint.php?saint_id=5

The Ecole Glossary: Matthias
- Brief paragraph on the New Testament figure.
- http://www2.evansville.edu/ecoleweb/glossary/matthias.html

Lives of the Saints: Saint Matthias, Apostle
- From Butler's Lives of the Saints.
- http://www.ewtn.com/library/MARY/MATTHIAS.htm

James Kiefer's Christian Biographies: Matthias the Apostle
- Profile. Includes prayer in traditional and contemporary language.
- http://elvis.rowan.edu/~kilroy/JEK/02/24.html

Vietnamese Eucharistic Youth Society: St. Matthias
- Short version of the life of this disciple, for children.
- http://www.tntt.org/vni/tlieu/saints/St0514.htm

Our Patron
- About Pennsylvania parish's patron, St. Matthias.
- http://www.saintmatthias.org/patron.html

Catholic Encyclopedia: St. Matthias
- The Apostle, in Scripture and legend.
- http://www.newadvent.org/cathen/10066a.htm

Patron Saints Index: Matthias the Apostle
- Illustrated profile, with links.
- http://www.catholic-forum.com/saints/saintm17.htm