The easyJet media account is believed to include its UK business, which spent £8m on ads in the 12 months to August 2010, and activity in Germany, France, Italy, Spain and the Netherlands.
The low-cost airline started the review of its agency arrangements in November 2009, as OMD's second three-year contract was coming to an end.
EasyJet appointed OMD in 2003 following a competitive pitch that culminated in a head-to-head with Carat.
Last week it was announced that easyJet was set come to an agreement with its founder Sir Stelios Haji-Ioannou, which would involve paying him an annual royalty in return for retaining the "easy" brand name, after three years of costly disputes that have taken the two parties to the High Court this year.
In September, Haji-Ioannou announced he would be launching easyGym, a cut-price, no frills chain of gyms across the UK, with the aim of undercutting premium-priced city gyms that also feature swimming pools and saunas.