The account was previously held by BD Network.
The win will see iris launch retail marketing campaigns over the next two years and experiential and instore activity within Orange stores and that of its partners.
Spencer McHugh, brand director at Orange UK, said: "After an extremely competitive pitching process, we are delighted to have chosen iris to be our sole agency for our retail marketing activities.
"They showed a real understanding of the telecoms and youth market and delivered some excellent work during the pitch process and we are excited to see more."
This article was first published on campaignlive.co.uk