If the government replaces the prime minister in a leadership spill, are they required to call an election?
Thank you for your question!
An election does not need to be held if the Prime Minister is replaced as party leader by their party.
The Prime Minister is a member of the House of Representatives who leads the party or coalition of parties with the support of the majority of members in the House of Representatives. If the Prime Minister was replaced as party leader, the new leader would become Prime Minister.
Role of the Prime Minister in Australia.

Parliamentary Education Office (peo.gov.au)
Description
This graphic shows that the Prime Minister is the most senior minister in the Australian Government as well as being key spokesperson for Australia, the head of Cabinet and the leader of the government.
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