The DUP has revealed that Derry councillor Maurice Devenney will replace William Hay as MLA for Foyle.
Former Assembly Speaker Hay resigned his seat earlier this month for health reasons.
Mr Devenney has been a Derry city councillor since 2005 and was Mayor of the city in 2011-2012.
First Minister Peter Robinson said he was “delighted” to welcome the party’s newest MLA.
“When William Hay decided to step down from the Assembly, the Democratic Unionist Party lost a dedicated and hard-working constituency representative,” he said.
“I am delighted, however, that the DUP will continue to be represented by someone well known to the people of Londonderry and with a track record of delivering for the community.”