Treasurer Gladys Berejiklian will put her hand up for the state's top job following NSW Premier Mike Baird's shock resignation.
Ms Berejiklian will release a statement on Thursday afternoon declaring that she is running for the leadership of the NSW Liberal Party and premier, a government source has confirmed to AAP.
The current deputy leader was reportedly seen having coffee with Mr Baird just hours before he dramatically announced he was quitting politics via social media on Thursday morning.
"Ms Berejiklian feels today is Mike's day but wanted to make it clear that she will run for the leadership," the source said.
It's unclear if the treasurer will face any challengers, but it's believed Transport Minister Andrew Constance was sounding out support for a tilt.
Another possible contender, Planning Minister Rob Stokes, is currently overseas.
Ms Berejiklian would become NSW's second female premier if elected. The Labor Party's Kristina Keneally served in the top job from 2009 to 2011.
Elected to Sydney's lower north shore seat of Willoughby in 2003, Ms Berejiklian is an experienced politician who has overseen massive surpluses and a strong budget performance as state treasurer.
The former transport minister has remained largely scandal-free during her career, and it's likely her personal background as the daughter of working-class Armenian migrants who attended a public school would rate highly with voters.
Mr Baird would not nominate a successor following his announcement on Thursday but said he would vote in the ballot.
The state's Deputy Premier and Nationals leader John Barilaro said he believed Ms Berejiklian would make a fantastic premier.
"I think the question will be, 'can the media pronounce Berejiklian - Barilaro government?'," he joked with reporters in Sydney.
"But she is a fantastic leader and there are others in the Liberal Party that are touted that could be committed to leadership and I will committed to working with whoever the leader may be," he said.