Communities using the Tridentine Mass

The following priestly societies and religious institutes use some pre-1970 edition of the Roman Missal or of a similar missal. Those not in communion with the Holy See are marked as "canonically irregular". Most use a pre-1970 edition of the Roman Missal, but some follow the proper missal of the Dominican Rite or the Carmelite Rite and thus celebrate not the Tridentine Mass but a form of liturgy permitted under the 1570 papal bull Quo primum.

The use of a pre-1970 Roman Missal is not prohibited by the current rules of the Catholic Church. See Tridentine Mass which contains much information about the format of a Tridentine Mass and the history of the various Missals of the Roman Rite.

They are dedicated to preserving older liturgical rites of the Roman Catholic Mass. Those approved by the Pontifical Commission Ecclesia Dei are sometimes called Ecclesia Dei Communities.

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