Hill joins from BBDO New York, where she was the executive vice-president and managing director, with responsibility for the Visa USA business. BBDO lost the Visa account in November last year.
The appointment is the latest in a string of executive-level reshuffles at the troubled Interpublic agency.
In March this year, Stephen Gatfield was named as the global chief executive, replacing Tony Wright, who moved to the chairman's position. Earlier this year, Sal Taibi was promoted from director of client services to become the president of the New York office.