Keith Turner has been co-opted onto Mid and East Antrim Borough Council for the Ulster Unionist Party.
Mr Turner will fill the seat vacated by Mark McKinty in the Larne Lough DEA.
Mr McKinty resigned from the party last month after being caught drink driving in the Ballypollard Road area of Larne on July 5.
Keith Turner stood for the party in the Braid DEA of Mid and East Antrim in May’s council election.
He secured 800 first preference votes, but failed to meet the quota of 1,106 after receiving transfers.
Announcing his co-option in a post on social media, Cllr Turner said: “I have been appointed as a councillor for the Larne Lough DEA on Mid and East Antrim Borough Council.
“I will follow on in the tradition of all the Ulster Unionist elected representatives in working tirelessly for everyone regardless of political persuasion, creed, colour, faith or gender to make where we live the best place possible.”