Named after Harlaxton House, the nineteenth century residence of Francis Thomas Gregory (1821-1888) explorer, Commissioner of Crown Lands, Darling Downs and MLC 1874-88. Harlaxton was used by the Governor of Queensland, Lord Lamington, as a summer residence 1896-1901.
Named and bounded by Queensland Place Names Board 1 June 1981. Named and bounded by the Minister for Natural Resources 21 July 2000. Locality re-gazetted by an Amendment Notice published in the Government Gazette on the 5 April 2012 due to the council amalgamations under the Local Government Reform Implementation Act 2007. Boundary amendment between Harlaxton and Mount Lofty, via action #17092, effective from 11/04/2018.