The National Trust of Australia, officially the Australian Council of National Trusts (ACNT), is the Australian national peak body for community-based, non-government non-profit organisations committed to promoting and conserving Australia's Indigenous, natural and historic heritage. The umbrella body was incorporated in 1965, with member organisations in every state and territory of Australia.

Modelled on the National Trust for Places of Historic Interest or Natural Beauty and inspired by local campaigns to conserve native bushland and preserve old buildings, the first Australian National Trusts were formed in New South Wales in 1945, South Australia in 1955 and Victoria in 1956; followed later in Western Australia, Tasmania and Queensland.^[1] The two Territory Trusts were the last to be founded, in 1976 (see below).

The driving force behind the establishment of the National Trust in Australia was Annie Forsyth Wyatt (1885–1961). She lived for much of her life in a cottage in Gordon, New South Wales, which is still standing. She was living in the Sydney suburb of St Ives when she died.

The organisation was incorporated in 1965. The umbrella body federates the eight autonomous National Trusts in each Australian state and internal self-governing territory, providing them with a national secretariat and a national and international presence.^[2][3]

The trust is Australia's national peak body for community-based, non-government non-profit organisations committed to promoting and conserving Australia's Indigenous, natural and historic heritage.^[4]

Collectively, the constituent National Trusts own or manage over 300 heritage places (the majority held in perpetuity), and manage a volunteer workforce of 7,000 while also employing about 350 people nationwide, as of 2020^[update]. Around 1,000,000 visitors experience the properties and their collections in Australia each year.^[5]

As of 2020^[update], the National Trust's constituent organisations were:

• List of National Trust properties in Australia
• List of Australian Living Treasures
• SAHANZ, the Society of Architectural Historians, Australia and New Zealand
• Historic Houses Trust of New South Wales