The Reformation, also known as the Protestant Reformation, was the 16th century schism within Western Christianity initiated by Martin Luther, John Calvin, and others
Reformation may also refer to:
- Movements connected to the Protestant Reformation:
- English Reformation, series of events in 16th century England by which the church in England broke away from the authority of the Pope and the Roman Catholic Church
- Icelandic Reformation, King Christian III of Denmark's imposition of Lutheranism, in the middle of the 16th century
- Reformation in Denmark–Norway and Holstein, the 16th century transition to Lutheranism in the realms ruled by the Copenhagen-based House of Oldenburg
- Reformation in Switzerland, the Protestant Reformation in Switzerland, during the 1520s
- Scottish Reformation, part of the wider Protestant Reformation, in 1560
- Swedish Reformation, the Protestant reformation in Sweden, in 1527
- Radical Reformation, an Anabaptist movement concurrent with the Magisterial Protestant Reformation
- Counter-Reformation (also known as the Catholic Reformation), the period of Catholic revival beginning with the Council of Trent, in response to the Protestant Reformation
- Evening Light Reformation, part of the holiness movement that led to the formation of the Church of God (Anderson, Indiana)
- Liberalism and progressivism within Islam (also known as Islamic Reformation), a variety of movements to reform Islam in the 20th and 21st centuries
- Mormon Reformation, a movement in Utah Territory in 1856–57
- Bohemian Reformation (also known as the Czech Reformation or Hussite Reformation)
- Reformation, a term commonly used in the United States for the Rectification (law) of a written contract or legal instrument
- Post-Suharto era or period of Reformasi (Reform), the (current) era in Indonesia following the 1997 Asian financial crisis and the fall of Suharto, characterized by increased freedom and political participation
- Reformation of hydrocarbons in chemistry, see Catalytic reforming