The Free Presbyterian Church of Ulster is a Presbyterian Christian denomination founded by Ian Paisley in 1951. Doctrinally, the church describes itself as fundamentalist, evangelical, and separatist, and is part of the reformed fundamentalist movement. Most of its members live in Northern Ireland, where the church is headquartered, and in County Donegal. The church has additional congregations in the Republic of Ireland, Great Britain and Australia, and a sister denomination in North America, the Free Presbyterian Church of North America, which has congregations in Canada and the United States. It also has a sister denomination in Nepal which was formed from the Nepal mission to the Unreached in November 2013.
John Armstrong was Deputy Moderator of the General Assembly of the Church, and became Moderator in 2020, with Colin Mercer from Omagh as Deputy Moderator; Armstrong succeeded Gordon Dane, minister of the founding church in Crossgar.