The agency won the business after a final shoot-out with Bartle Bogle Hegarty.
Wieden & Kennedy and TBWA\London were knocked out of the running at an earlier stage.
The pitch, which kicked off in January this year, was handled by the AAR. The pitch was overseen by Moneysupermarket.com's recently appointed director of consumer marketing, Paul Troy.
The previous incumbent, Dare, did not re-pitch for the business.