Bill Shorten will be re-endorsed as Labor leader, but the position will still be thrown open at a caucus meeting on Friday.
Under rules proposed by Kevin Rudd and endorsed by the ALP in 2013, the Labor leadership must be spilled in the event of an election loss.
A Labor source told AAP the party would be "breaking the law" if the leadership wasn't spilled.
Election counting on Thursday was pointing to the return of the Turnbull government with 76 seats in the 150-seat parliament.
It's been speculated that Mr Shorten's 2013 leadership ballot contender Anthony Albanese, who hails from the Left faction, would re-contest the ballot.
But Mr Albanese has ruled it out for the moment and will instead move a motion at the caucus meeting in Parliament House giving Mr Shorten the authority to negotiate with crossbenchers in the new parliament.
The motion will effectively unify the caucus behind Mr Shorten to lead the party into the 45th parliament and indicate no one will challenge him.
It will also operate if Mr Shorten finds himself seeking the numbers in parliament to form a minority government.
Nominations will open on Friday and close the following Friday.
The Left will also be seeking an extra frontbench position following the retirement of a higher proportion of Right faction MPs and the success of Left candidates at the election.
Tasmanian senator Helen Polley tweeted on Thursday: "Excited to be heading to (Canberra) for first caucus meeting. Labor is united behind Shorten."
Shadow treasurer Chris Bowen said Labor would be a "strong and unified opposition".
