Sam Mézec will stand for the role of Chief Minister in Jersey.
Reform Jersey's parliamentary party unanimously agreed to put forward their leader for the top job at their first meeting since the election.
The party will publish a full statement on Monday 27 June setting out its intention to form the island's next government.
In a statement, the party said: " We believe that the election result clearly shows that there is widespread public support for positive change. Only Reform Jersey can provide that change."
It comes after his party doubled their representation in the States Assembly on a successful night at the polls, picking up a further five seats.
He becomes the third candidate to announce they will stand for the role with Kristina Moore and JLC leader Philip Bailhache already confirming their intention to stand.