Former federal small business minister Bruce Billson says his demotion at the hands of Prime Minister Malcolm Turnbull triggered his move to quit politics at the next election.

Mr Billson revealed the news to colleagues at this morning's party room meeting.

He told the ABC that he did not resent being dropped from the Cabinet, but had been considering his options since the ousting of former prime minister Tony Abbott.

"I have no bitterness about that decision, it certainly wasn't one that I'd hoped for," he said.

"But it did trigger a reflection."

After almost 20 years in parliament, Mr Billson said he had been feeling "very much in the driver's seat" on policy prior to the leadership spill in September.

He said he probably would not be leaving politics if he had not been demoted.

"I loved what I was doing, but I was not able to keep doing what I loved," he said.

In a statement, he said he had reflected on the circumstances following the Liberal leadership change and had decided it was the right time to "hang up the campaign RM Williams".

Mr Billson said he planned to spend more time with his family.

"To be able to work 'selflessly' for your community and nation is what is required and rightfully expected," he said.

"However, to do so requires a 'selfishness' in terms of availability and intellectual focus which family experience as being physically and mentally 'away' an awful lot and for key events.

"While the impact on our family has been profound, we have been nourished and comforted by knowing it was all for the pursuit of meaningful goals and delivering better outcomes for our Dunkley community and our nation.

"My sincere appreciation and heartfelt thanks goes out to my sweetheart Kate, my children, the incredibly talented and committed staff I have had the good fortune to work with, the Liberal Party, my campaign team, supporters and all those whose advice, support and wise counsel has made possible my parliamentary career and the honour of representing the community in which I grew up.

"I have loved these days and make public this decision with no regret, remorse or bitterness," he added.

Mr Billson has previously held numerous roles in a diverse range of portfolios, including in veterans affairs, defence, foreign affairs and trade, immigration, and Indigenous and multicultural affairs.

Prime Minister Malcolm Turnbull offered him another portfolio when he won the Liberal leadership, but Mr Billson declined.