The capital will elect three lower house members for the first time in 23 years on May 18 after a redistribution by the Australian Electoral Commission last year.

On Wednesday officials at the Commission officially declared the candidates, as well as where they will appear on the ballot paper.

The major party candidates have been preselected for some months, with Labor's Andrew Leigh, the only incumbent MP on the ballots, recontesting his seat of Fenner. He will be challenged by the Liberals' Leanne Castley and the Greens' Andrew Braddock and two minor party candidates.

In Canberra, former staffers Alicia Payne for Labor and Tim Hollo for the Greens are campaigning hard, while Mina Zaki has been hitting the pavement for the Liberals. Former Bullet Train party leader Tim Bohm is running for Canberra as an independent.

Eight candidates are running in Bean, including former senator David Smith for Labor, Ed Cocks for the Liberal Party and Jonathan Davis for the Greens. Jamie Christie is running as an independent, while Matt Donnelly is representing the Liberal Democratic Party and Ben Rushton the Great Australian Party.

Mr Rushton had previously been advertised as a candidate for the United Australia Party, which is led by Clive Palmer. He said on Wednesday he had moved to the Great Australian Party, which is connected to former One Nation senator Rod Culleton, who was removed from the Senate by the High Court. Mr Rushton described the party as a "constitutional party".

Clive Palmer's United Australia Party has candidates in all three lower house seats in the ACT, including Tony Hanley in Bean, Greg De Maine in Canberra and Glen Hodgson in Fenner. The party is also running for the Senate in the ACT.

The Australian Progressives are also running in all three lower house seats, with Therese Faulkner in Bean, Robert Knight in Canberra and Kagiso Ratlhagane in Fenner.

Liberal senator Zed Seselja will take on his old foe Katy Gallagher as she attempts to win back her Senate spot, and the Greens are hoping to knock off Senator Seselja and put Penny Kyburz in the Senate.

Fewer minor parties are running for the Senate in the ACT than in other states, but Sustainable Australia and Fred Nile's Christian Democratic Party will be represented on the ballot.

Controversial hard right senator Fraser Anning's party, called Fraser Anning's Conservative National Party, is running two candidates in the ACT Senate race, including Shane Van Duren who has a criminal history.

Anthony Pesec and running mate Gary Kent are running as independents, as is Nick Houston from the Democratic Reform Alliance and former VFL footballer Gary Cowton.

Pauline Hanson's One Nation party has no candidates in the ACT.

The full list of candidates and ballot positions is available on the Electoral Commission website.