OMD lost the telecom giant's UK account at the beginning of the year when it was moved into Carat.
It now holds not only the UK business, worth an estimated £58 million, and the company's global media account. This covers all global markets where Vodafone is a wholly-owned business.
Vodafone has also shifted its global creative ad account from BBH to Santo, the little-known Argentinean ad agency backed by WPP. However it said BBH would remain Vodafone's UK ad agency.