Mills will lead the operation selling integrated advertising opportunities across talkSPORT and Sport.
He will report to Calum Macaulay, who joined as the managing director of talkSPORT in January. Kurt Edwards, the commercial director, will report to Mills.
Mills was most recently the commercial director at Mountain Media. He has also worked at Carlton Screen Advertising.
Bullock left UTV Media in January to launch CONTENTed with talkSPORT’s former programming director Moz Dee.