The first House of Representatives was elected on 30 March 1901. All the members elected to that First Parliament therefore had equal seniority. It follows that there could not be a "longest-serving member" until only one member from the First Parliament was still in the House. That occurred on 8 April 1935 with the death of David Watkins.

Since that date the longest-serving members of the House of Representatives have been:

• Rt Hon Billy Hughes: first elected 30 March 1901, died 28 October 1952
• Rt Hon Sir Earle Page: first elected 13 December 1919, defeated 9 December 1961
• Hon Eddie Ward: first elected 7 March 1931, defeated 19 December 1931, again elected 6 February 1932, died 31 July 1963

• Rt Hon Sir John McEwen: first elected 15 September 1934, resigned 1 February 1971
• Rt Hon Arthur Calwell: first elected 29 September 1940, retired 2 November 1972
• Hon Fred Daly: first elected 28 August 1943, retired 11 November 1975
• Hon Kim Beazley senior: first elected 18 August 1945, retired 10 November 1977

• Rt Hon Sir William McMahon: first elected 10 December 1949, resigned 4 January 1982