Premier David Alward has called a byelection in Rothesay for June 25, nine days after former Progressive Conservative MLA Margaret-Ann Blaney quit politics to take a job at Efficiency NB.
Alward announced the byelection at Government House in Fredericton on Friday.
The Progressive Conservatives have held the Rothesay riding, and its predecessor Saint John-Kings, since 1999.
The Tory nominating convention for the byelection will be June 2, while the Liberals, who are currently in the middle of a leadership race, will hold their nominating convention on June 5.
The premier said he feels good about his party's chances.
"Look, I am proud of the work – that we have begun to rebuild the province of New Brunswick," Aylward said. "We believe we have an excellent story to tell. We are looking forward to the dialogue with the people of Rothesay in the coming weeks."
It could be an opportunity for the Liberals to elect a woman to join their all-male caucus.
Liberal leader Victor Boudreau said Rothesay voters should ask themselves whether they want to elect yet another Conservative in the region.
"Every riding is now represented by a Tory MLA, and I think that people from Rothesay and from the Greater Saint John area have to ask themselves, 'are they any better off today than they were two years ago?'", Boudreau said.
"I would suspect the answer to that question is no."
It's unclear if NDP Leader Dominic Cardy will accept interim Liberal Leader Victor Boudreau's challenge and run in the byelection.
Boudreau argued it's an opportunity for Cardy to have a seat in the house.
Cardy has said he will consider running in the southern New Brunswick riding.
The NDP has been without a seat in the legislature since Elizabeth Weir resigned in 2005.
Alward had six months to call a byelection.
The Elections Act says a writ period has to be between 28 and 38 days.
The Progressive Conservatives have 41 seats in the legislature and the Liberals have 13 seats.