Jay Wilson Weatherill is a former Australian politician who was the 45th premier of South Australia, serving from 21 October 2011 until 19 March 2018. Weatherill represented the House of Assembly seat of Cheltenham as a member of the South Australian Labor Party from the 2002 election to 17 December 2018, when he retired.

The premier of South Australia is the head of government in the state of South Australia, Australia. The Government of South Australia follows the Westminster system, with a Parliament of South Australia acting as the legislature. The premier is appointed by the governor of South Australia, and by modern convention holds office by virtue of their ability to command the support of a majority of members of the lower house of Parliament, the House of Assembly.