As of 2021, a majority of Belair residents don't identify with a religion, with 59.2% of residents falling into the census category of "Secular Beliefs and Other Spiritual Beliefs and No Religious Affiliation". The most commonly stated religious affiliations in the 2021 census were Anglican (11.1%), Catholic (9.5%), and the Uniting Church (5.9%). Churches in the suburb include Holy Innocents Anglican Church Belair and Belair Uniting Church, both on the same road (Sheoak Road).
