The move follows criticism over rural branch closures and job cuts - and marks the first time the BBA has retained an external PR agency.
The BBA, which represents nearly 300 banks, hired Blue Rubicon after a four-way pitch. Blue Rubicon MD Fraser Hardie said the remit involves PR for the industry and the BBA itself.
The appointment comes after the BBA released the results of its research into the decline of the reputation of banks, which showed customers in the 50-plus age group were the most disillusioned with them.
BBA director of communications Simon Pitkeathley said: 'Initial efforts will focus on the grass-roots role banks play, particularly on the industry's work with SMEs, which employ more than half the UK workforce.'