The re-appointments follow a statutory internal review of the business.
BBH has worked with BA since 2005. It will continue as British Airways' global advertising agency, supporting brand communications across the world.
OgilvyOne, the airline's digital and direct agency, will continue to work on the airline's global loyalty and below-the-line marketing activity.
Abigail Comber, head of brand engagement, BA, said: "I am delighted to be continuing our strong relationship with BBH. We have exciting brand communications projects ahead of us which they will play a pivotal role in."
Ian Romanis, head of customer engagement, BA, said: "Over the past three years we have developed a strong partnership with OgilvyOne and have continued to be impressed by their strategic capability, creativity and value they have added to our business."