A pro-cathedral is a parish church that is temporarily serving as the cathedral or co-cathedral of a diocese or has the same function in a Catholic missionary jurisdiction that is not yet entitled to a proper cathedral, such as an apostolic prefecture or apostolic administration. It is distinct from a proto-cathedral, the term in the Roman Catholic Church for a former cathedral, which typically results from moving an episcopal see to another (usually new) cathedral, in the same or another city. In a broader context, the term 'proto-cathedral' may be used of a church used by a bishop before a settled cathedral (or pro-cathedral) has been designated.
In Ireland, the term is used to specifically refer to St Mary's Pro-Cathedral in Dublin, the seat of the Roman Catholic Archbishop of Dublin since the Anglican Reformation in Ireland, when Christ Church Cathedral and St Patrick's Cathedral were occupied by the new (Anglican) Church of Ireland.
In Scotland, the term is used to refer to St Mary's Pro-Cathedral in Edinburgh, the seat of the Roman Catholic Archbishop of Saint Andrews and Edinburgh, as the original St Andrews Cathedral was abandoned after the Scottish Reformation in 1560 and is currently in a ruinous state. St Andrew's Pro-Cathedral in Glasgow has been the seat of the Roman Catholic Archbishop of Glasgow since 1889. The original Glasgow Cathedral however had been re-established as the Church of Scotland’s High Kirk of Glasgow after the Scottish Reformation.
Details of some 15 former pro-cathedrals (11 Roman Catholic and 4 Anglican) can be found in the List of former cathedrals in Great Britain.
In Spain, the Colegiata de San Isidro, Madrid served as the provisional cathedral for the Roman Catholic Archdiocese of Madrid from its creation in 1885 until 1993, when Pope John Paul II consecrated the newly completed Almudena Cathedral.
In Albania, the Albanese Apostolic Administration of Southern Albania had the Kisha e Shën Maria dhe Shën Luigji, in Vlore, as only episcopal see of its Eastern Catholic particular sui jurus Albanian Catholic Byzantine Church.
In the Philippines, the Episcopal Diocese of the Central Philippines had the St. Stephen's Parish in Tondo, Manila as its pro-cathedral before the see was transferred to the Cathedral of Saint Mary and Saint John in Quezon City. Also, in February 2012, the Pro-Cathedral Church of San Fernando de Dilao became the Pro-Cathedral of the Archdiocese of Manila, until the structural renovations of Cathedral-Basilica of the Immaculate Conception on March 25, 2014. The cathedral was reopened to the general public on April 9, 2014.
The Cathedral of the Holy Name, Mumbai, was previously the pro-cathedral of the Holy Name.
In San Luis Obispo CA, the parish church of Old Mission San Luis Obispo de Tolosa and in Salinas, CA, the parish of Madonna Del Sasso, were both elevated to pro-cathedral status by the late Bishop Richard Garcia.
In Qu'Appelle, Saskatchewan, the parish church of Saint Peter's was the pro-cathedral for the Anglican southern Saskatchewan diocese until 1944. From 1944 to 1979, St. Paul's Cathedral served as the pro-cathedral before it was elevated to cathedral status.
In the United States, the church of St. Paul the Apostle in Savannah, Georgia, is the pro-cathedral for the Episcopal Diocese of Georgia. The Cathedral of the Incarnation (Baltimore) was a pro-cathedral for 35 years before the Episcopal Diocese of Maryland passed a resolution in 1955 for it to become the diocesan cathedral. St. Stephen's Episcopal Church in Wilkes-Barre, Pennsylvania, was designated the pro-Cathedral in the Episcopal Diocese of Bethlehem in 1999 and as the Pro-Cathedral by the Presiding Bishop and the President of the House of Deputies of The Episcopal Church in 2001. St. Bartholomew's Anglican Church in Tonawanda, NY became a Pro-Cathedral on August 12, 2011 as part of the North American Anglican Conference, and is the seat for Bishop Bill Atwood.
St. Luke's Ministries in Copley, Ohio, is the Pro-Cathedral for the Anglican Diocese of the Great Lakes under Bishop Ronald W. Jackson.
In Christchurch, New Zealand, St Mary's has become the pro-cathedral of the Christchurch Catholic Diocese, in place of the Cathedral of the Blessed Sacrament which is closed because of severe damage caused by the 2011 Christchurch earthquake.
Holy Cross Pro-Cathedral in Vanimo, West Sepik, Papua New Guinea, the see of the Roman Catholic Diocese of Vanimo