Miller, who starts with immediate effect, will head up the Barclays direct marketing account for the agency.
His responsibilities include managing all of Barclays' retail product areas, which include savings, lending, insurance, current accounts and home finance. He will report to Tash Whitmey, managing partner at .
In his previous role at Draftfcb, Miller managed the client services department in addition to specific client responsibilities in the financial, technology, travel, retail and charity sectors.
Miller, who parted company with Draftfcb last year, said: "EHS Brann has some of the best minds in the business, both strategically and creatively. The agency is producing great work at the moment with a strong proposition with direct, digital and data offerings. I'm glad to be part of that team."
Whitmey said: "Tony brings a wealth of experience and energy to the agency. His addition will further ramp up our expertise at a senior level adding to our considerable line-up."
Separately, Angus Crowther has been promoted to the newly created role of new-business and marketing director from client partner.
Crowther's new responsibilities include new-business, developing existing business, as well as continuing to head up the Barclaycard and Barclaycard International accounts.
Crowther, who has been with EHS Brann since 1999, will also join the management board.