The SDLP has co-opted Ryan Wilson onto Antrim and Newtownabbey Borough Council.
Mr Wilson will take up the vacant seat in the Dunsilly DEA.
It had been vacant since former SDLP representative, Brian Duffin, resigned from the local authority after losing an appeal against a sexual assault conviction.
Mr Wilson said: “I am delighted to have been co-opted to serve the people of Randalstown, Toome, Creggan and Parkgate, in what is an increasingly challenging time in politics.
“Alongside my colleagues in council, I intend to make rural job creation a focus during my tenure, as well as lobbying for more social housing to be built in South Antrim.
“Additionally, I will work to secure adequate funding for many excellent community, charitable and sporting organisations throughout the constituency.”
Welcoming Mr Wilson to the role, party leader Colum Eastwood MLA said: “Ryan has proven to be a dedicated activist within the party and his local community. I know he’ll play a key role in the South Antrim area.
“It is an exciting time to be in politics and I am confident Ryan will grasp the challenge with both hands.”