BHF selected Partners and Mother from an original shortlist of five, and has been testing their respective strategies with smokers for the past two months.
The agencies' brief was to produce work that would heighten awareness of smoking as a major risk factor in heart disease.
The BHF business accounts for one half of the £15 million the Government had earmarked to warn the public about the dangers of smoking. The other half went through Cancer Research UK, which appointed Bartle Bogle Hegarty earlier this year following a competitive pitch.
Betty McBride, the director of marketing and communications at the British Heart Foundation, said: "The brief was to be hard-hitting. I believe the Partners' work will be real solar plexus stuff for smokers."
The Partners BDDH managing director, Simon Toaldo, who led the agency's pitch, said: "This is a superb win for us. We look forward to working with the British Heart Foundation to produce a campaign that will really make a difference."
Partners BDDH is a BHF roster agency, having been appointed to replace Abbott Mead Vickers BBDO in November 2002. Recent wins include Travelodge as well as the advertising business for the US household cleaning product manufacturer Orange Glo.
In addition to Partners BDDH, BHF has also appointed Target Direct to handle its direct marketing business following a four-way pitch.