The four-year-old consumer agency beat off established rivals to scoop the prestigious gold award, with the judges citing its impressive growth and high conversion rate.
Mitchell Kaye's agency was also commended for innovative campaigns - including making philosopher Alain de Botton London Heathrow Airport's first writer-in-residence.
Last year's winner Edelman was highly commended, as was Lansons Communications. Also on the shortlist for the award were Blue Rubicon and Cirkle.