AMV BBDO beat off M&C Saatchi and Bartle Bogle Hegarty to win the business in a final pitch, which took place last week.
Ahead of the final decision, Dixons hired the former O2 marketer Gary Booker as its chief marketing officer to replace Andrea Silver, who is leaving the retailer to pursue other interests.
The result ends Dixons's 25-year relationship with Saatchi agencies. It was a founding client of M&C Saatchi in 1995. Before that it had been a client of Saatchi & Saatchi since at least 1988 and moved with Saatchi brothers Maurice and Charles when they left the agency to found M&C Saatchi.
Dixons called the pitch in September and the Dixons procurement team led the process.
Dixons spent £46.8 million on advertising in the UK in the 12 months to September 2013, according to Nielsen.
The review aimed to identify opportunities for the group to grow, after it reported positive financial results last year. Underlying pre-tax profits for the UK and Ireland were up 39 per cent in the year to April 2013.
M&C Saatchi has been behind work such as 2012's animated "we can help" campaign for Currys and PC World, which was set in a futuristic space-inspired environment.
In 2010, the agency’s "the last place you want to go" work for The Dixons website was named the most-awarded print campaign of the year by The Gunn Report.
No one at AMV would comment on the news. Dixons Retail Group also did not respond to request for comment by the time of publication.