List of Australian heads of government by time in office Historical premiers Historical premiers

| Rank_ | State_ | Premier_ | Party_ | Assumed_office_ | Left_office_ | TOTAL_Time_in_office_ |
|---|---|---|---|---|---|---|
| 1. | SA | Sir Thomas Playford (1896–1981) GCMG | Liberal & Country League | 5 November 1938 | 10 March 1965 | 26years, 125days |
| 2. | QLD | Sir Joh Bjelke-Petersen (1911–2005) KCMG | Country & National Parties of Australia | 8 August 1968 | 1 December 1987 | 19years, 115days |
| 3. | TAS | Sir Robert Cosgrove (1884–1969) KCMG | Australian Labor Party | 18 December 1939 | 18 December 1947 | 18 years, 182 days |
| 3. | TAS | Sir Robert Cosgrove (1884–1969) KCMG | Australian Labor Party | 25 February 1948 | 26 August 1958 | 18 years, 182 days |
| 4. | VIC | Sir Henry Bolte (1908–1990) GCMG | Liberal & Country League | 7 June 1955 | 23 August 1972 | 17years, 47days |