This is a list of aircraft produced or proposed by Geoffrey de Havilland or designed at the de Havilland Aircraft Company from its founding in 1920 until its purchase by (and integration into) the Hawker Siddeley Group in 1959. The designs DH.121 and DH.125 which were under development when de Havilland lost its separate identity under Hawker Siddeley kept their numbering and were produced as the Hawker Siddeley HS-121 Trident and the Hawker Siddeley HS.125. The list does not include aircraft designed by de Havilland Canada or de Havilland Australia, founded as de Havilland subsidiaries.