The Uniting Church in Australia (UCA) was founded on 22 June 1977, when most congregations of the Methodist Church of Australasia, about two-thirds of the Presbyterian Church of Australia and almost all the churches of the Congregational Union of Australia united under the Basis of Union. According to the church, it had 243,000 members in 2018. In the 2016 census, about 870,200 Australians identified with the church; in the 2011 census, the figure was 1,065,796. The UCA is Australia's third-largest Christian denomination, behind the Catholic and the Anglican Churches. There are around 2,000 UCA congregations, and 2001 National Church Life Survey (NCLS) research indicated that average weekly attendance was about 10 per cent of census figures.

The UCA is one of Australia's largest non-government provider of community and health services. Its service network consists of over 400 agencies, institutions, and parish missions, with its areas of service including aged care, hospitals, children, youth and family, disability, employment, emergency relief, drug and alcohol abuse, youth homelessness and suicide. Affiliated agencies include UCA's community and health-service provider network, affiliated schools, the Uniting Aboriginal and Islander Christian Congress, Frontier Services and UnitingWorld.