Iris beat Atomic in a final shoot-out after the brand called a review at the end of last year. Creature of London and Gravity Road had pitched earlier on in the process, which was handled by AAR.
The brand called a review at the end of last year, having appointed a number of new marketers in the last 12 months.
In August, Stephan Croix joined as chief sales and brand officer for Europe and the UK from Starwood Hotels, while Beverley D’Cruz became UK sales and marketing director at the same time.
D’Cruz, who ran the pitch, was previously marketing director at fellow Yum! brand KFC in Canada.
Iris was very well-placed to capture the business given its five-year record of working on Domino’s, the market leader in UK pizza delivery. Domino's ad account moved to VCCP following a pitch last year.
The Cheil-owned agency has now been tasked with redefining and launching a new brand across above-the-line, customer experience and digital.
D'Cruz said: "Iris understands this category through and through. Their innovation smarts and digital first thinking stood out during the pitch process, and they left us in no doubt that they will a passionate partner agency to make Pizza Hut the number one in the UK.".
However, the sector has been disrupted in recent years by the likes of Just Eat and Deliveroo, which are gaining market share and have upped their marketing activity.
Food delivery companies have also been impacted by ingredient cost inflation since the pound weakened following the Brexit vote in 2016.
The account moves from Ogilvy & Mather London, which had worked on Pizza Hut’s delivery service advertising since 2014. Last year the WPP agency created a nostafic ad campaign featuring Rainbow children's show characters Bungle and Zippy.
Iris London managing director Chris Marlow said: "We have had a lot of fun working in this category, achieving 12 quarters of double-digit growth for Domino’s along the way. This brief from Pizza Hut could not have been more motivating and calls on the forward-thinking disruptive approach that is second nature for Iris."