The agency won the business after a competitive pitch against Stephens Francis Whitson and CMW.
It is the first account win for the agency since it was created by the merger of Digitas with Kitcatt Nohr, following the acquisition of the direct agency by Publicis in early March.
Kitcatt Nohr Digitas will be responsible for advertising across press, online and outdoor, and will target a business audience, including independent financial advisors.
The review, which began in February, was led by the Aviva global marketing and corporate affairs director, Paul Lockstone. It follows the appointment of CMW to handle Aviva's global digital activity last November.
Abbott Mead Vickers BBDO, which creates Aviva's consumer facing advertising, is unaffected by the appointment of Kitcatt Nohr Digitas. The agency's current campaign features the comedian Paul Whitehouse playing a range of characters to emphasise how important insurance is to families.
The company also uses a number of agencies for its direct marketing activity, including Proximity, Chemistry and CMW. ZenithOptimedia handles Aviva's media planning and buying account.
Aviva and Kitcatt Nohr Digitas were unavailable for comment.