Dean Young was on Monday elected in the southern electorate of Franklin, replacing fellow Liberal Jacquie Petrusma who retired in July to spend more time with family.

She was the fourth Liberal MP to quit politics since the party's re-election in May 2021, following the departure of Adam Brooks, Sarah Courtney and former premier Peter Gutwein.

Mr Young, who had an unsuccessful tilt at Canberra at the 2019 federal election, picked up 3,196 first-preference votes at the state election from more than 69,000 Franklin votes.

Tasmania is split into five electorates, each represented by five members.

Mr Young, a newsagency owner, finished ahead of former Huon Valley mayor and Liberal candidate Bec Enders in the recount.

His election comes a day before the resumption of parliament, which was postponed by Premier Jeremy Rockliff to avoid a minority in the lower house.

The Liberals, who were re-elected with 13 of 25 lower house seats, have been forced into several cabinet reshuffles this year.

As well as the four retiring MPs, upper house member Jane Howlett left cabinet in February after the death of her brother.

Ms Courtney and Mr Gutwein called time on lengthy political careers in February and April, respectively, for family reasons.

Mr Brooks quit shortly after the election after being charged with weapons offences by Queensland police.

The trio were replaced in parliament by Liberals Lara Alexander, Simon Wood and Felix Ellis.

Australian Associated Press