Vodafone has picked BMP DDB Needham to work alongside incumbent agency Leopard on its 15m business.
The agency is understood to have pitched against Duckworth Finn Grubb Waters.
Vodafone has been looking for an agency to replace Saatchi & Saatchi, which shared the account with business-to-business specialist Leopard until spring 1994.
Media will be handled by both agencies for the time being.
Vodafone went on TV last year with a campaign through Leopard created in August 1994, featuring actress Dawn French.
Total advertising spend on press, poster and TV last year was about 8.5m (Register-MEAL).
The company says it is not yet certain how the spend will be split between the two agencies.
Leopard says it expects to handle another 12m-13m on the account this year, while BMP will work on business worth a little less, bringing the total advertising spend up to about 20m.
Vodafone, however, says that most of its spend will move into consumer TV advertising.
As well as providing one of the main operating networks for mobile phones, Vodafone also offers a pager service and retail and direct sales.