^ abAt the November 1958 election Labor senator James Ormonde was elected to a full term seat, from 1 July 1959 to 30 June 1965 and Country Party candidate Colin McKellar was elected to fill the casual vacancy ending on 30 June 1962, giving the government a majority in the Senate.
^At the November 1958 election Country Party Senator Tom Drake-Brockman was elected to a full term from 1 July 1959 to 30 June 1965 and Liberal candidate George Branson was elected to fill the balance of the casual vacancy ending on 30 June 1959.
^The Australian Labor Party (Anti-Communist) changed its name to the Democratic Labour Party in 1957.
This is a list of members of the Australian Senate from 1956 to 1959.[1] Half of its members were elected at the 9 May 1953 election and had terms starting on 1 July 1953 and finishing on 30 June 1959; the other half were elected at the 10 December 1955 election and had terms starting on 1 July 1956 and finishing on 30 June 1962. The process for filling casual vacancies was complex. While senators were elected for a six-year term, people appointed to a casual vacancy only held office until the earlier of the next election for the House of Representatives or the Senate.[2]
^ abcLabor Senator Bill Ashley died on 27 June 1958; Labor member James Ormonde was appointed to fill the ensuing vacancy on 30 July, expiring at the November 1958 election. At the 1958 election, Ormonde was elected to a full term seat, from 1 July 1959 to 30 June 1965 and Country Party candidate Colin McKellar was elected to fill the casual vacancy ending on 30 June 1962.
^ abcCountry Party Senator Harrie Seward died on 23 July 1958; Country Party member Tom Drake-Brockman was appointed to fill the ensuing vacancy on 12 August, expiring at the November 1958 election. Liberal candidate George Branson was elected to fill the balance of the casual vacancy ending on 30 June 1959. Drake-Brockman was elected to a full term from 1 July 1959 to 30 June 1965.
^ abThe Australian Labor Party (Anti-Communist) changed its name to the Democratic Labour Party in 1957.
^ abLabor Senator Jack Devlin died on 26 May 1957; former Labor Senator Charles Sandford was appointed to fill the ensuing vacancy on 6 June, expiring at the November 1958 election, when he was elected to fill the balance of the vacancy ending on 30 June 1962.
^ abcdAppointed to a casual vacancy and only held office until the earlier of the next election for the House of Representatives or the Senate.[2]
^ abLiberal Senator John Spicer resigned on 13 August 1956 to be appointed to the Commonwealth Industrial Court; Liberal member George Hannan was appointed to fill the ensuing vacancy on 28 August, expiring at the November 1958 election, when he was elected to fill the balance of the vacancy ending on 30 June 1962.