The centre is readying activity ahead of its opening, which is scheduled for September 2011.
CHI and Made by Many, which presented in partnership, have been appointed to deliver the overall digital campaign. The Viral Factory will provide additional viral activity.
CHI had already been appointed to the advertising account for the centre, as well as the existing Westfield centre in West London in April.
Westfield Stratford City has a catchment of 4.1 million people and is anchored by a John Lewis, Waitrose and Marks & Spencer.