He first entered politics by serving on the Provincial Council of Otago from 1855 to 1865 before he was elected to the New Zealand House of Representatives as member for Roslyn in 1866.
His siblings were Andrew (29 June 1801 – 17 September 1873), Catherine Suttie (28 January 1805 – 1867 and Janet Reekie (28 November 1807 – ).
[2] In the new colony Hepburn took a deep interest in religious matters, and was erected on 16 March 1851 as an elder of First Church for the Halfway Bush district, and was session clerk for some years.
[2][11] He represented the Roslyn electorate from 1866 to 1869, when he resigned on the ground of ill-health[4] and was succeeded by Henry Driver on 12 February 1869 after a by-election.
George Hepburn died at his home on 9 December 1883[14] at the age of 80 and is buried in the Southern Cemetery in Dunedin.