Lloyds TSB Corporate Markets handed the brief to FD following an exhaustive five-stage pitch believed to have involved as many as 15 agencies.
It is thought the pitch came down to a two-way shoot-out between FD and Capital MS&L. Previous incumbent Grayling was understood to have been eliminated at an earlier stage.
The account, with the part state-owned banking giant, is understood to be worth a significant six-figure sum.
FD will report to Ian Kitts, head of media, for Lloyds' wholesale banking division. Kitts only joined Lloyds in September from law firm White & Case, where he was EMEA media relations and corporate comms manager.
He also previous worked for FD for three years before joining Simmons & Simmons in 2006.
FD's account will be led by Tony Danaher, UK MD of corporate and MD of FD's property advisory arm FD Tamesis.
The brief encompasses corporate media relations for Lloyds' financial institutions and major corporate groups. The agency will also handle media relations for its real estate arm, which has come under pressure in recent times following the absorption of HBOS's stressed real estate portfolio when the two banks agreed to merge in 2008.
The move comes after a similar process in Lloyds' insurance division, which handed a WPP-led coalition of agencies its corporate media relations and public affairs accounts in July. That decision came after previous comms head Shane O'Riordain stepped down to be replaced by former ITV comms chief Brigitte Trafford at the beginning of July.