C.S. Lewis belonged to Anglicanism after joining the Church of England.
Lewis returned to Christianity during the late 1920s and early 1930s and became an Anglican. His conversion was influenced by conversations with Christian friends, including J.R.R. Tolkien and Hugo Dyson, as well as his reading of Christian authors.
Although Lewis wrote widely read defenses of Christianity, he generally presented himself as an advocate of what he called “mere Christianity,” the common core shared by many historic Christian traditions. That phrase can make his personal affiliation seem less specific than it was.
Lewis was not a Roman Catholic or an Orthodox Christian. His Anglican identity shaped his participation in the Church of England and his role as a Christian apologist, while his books continued to attract readers from many denominations.