TBWA will be responsible for developing globaly digital, TV and print campaigns that highlight BNY Mellon's ability to manage, service and power global investments.
The global account, thought to be worth in the region of $30m, was previously held by the Omnicom-owned business-to-business communcations specialist Doremus & Co.
TBWA's London and New York offices collaborated on the pitch and the account will be run from New York, using the same collaborative model.
Judy Hu, chief marketing officer, BNY Mellon, said: "TBWA showed us stand-out strategic direction and great creative, as well as a truly collaborative global approach. We’re looking forward to partnering with them on cross-platform efforts that help us build our global brand."
Peter Souter, chief creative officer, TBWA\London, said: "This is a wildly exciting opportunity to help BNY Mellon receive the additional global brand recognition that it has earned through its incredible history and recent success."