The company appointed the group after a five-way pitch for the retained brief, with work to be led by M&C Saatchi PR.
The social media-specific brief was issued by Dixons Retail, which also owns the PC World and Currys brands, and comes amid a wider rethink around how the firm deals with its customers.
Chris Hides, MD of M&C Saatchi PR, said the agency would be working with M&C Saatchi's advertising arm to 'expand Dixons' social media presence'.
This includes creating content and managing communities for all of the retailer's social media channels, as well as striving to gain a new presence in social media spaces such as Pinterest.
Hides pointed to recent work by Dixons with rapper Tinchy Stryder around its Goji brand as an example of content that would be ideal for growing a social media stake. He said: 'That kind of content is very shareable.'
Amanda Clift, head of marketing at Dixons Retail, said: 'We have worked hard to become a retailer that is helpful and inspiring, and social media allow us to further demonstrate our commitment to these values.'