The account, which is understood to be worth in the region of $170m-$200m (£86m-£102m), will now be handled by the New York division of BBDO, after it was awarded by , which has around a 17% share of the North American consumer electronics market.
BBDO New York will be responsible for the account planning, ad strategy and media execution for Best Buy, following the retailer's decision to hand the account to an external agency.
Ruby Anik, senior vice-president of marketing and communications at Best Buy, said: "We believe this partnership with BBDO New York will enable us to support the company's aggressive growth goals and build to enhance our capabilities."
The agency, which won the Hertz account in March this year, also lists Sony Electronics among its major clients.
David Lubars, chairman and chief creative officer at BBDO New York, said: "We're psyched and humbled by Best Buy's confidence in us. We're looking forward to doing historical things together."
Best Buy, which employs around 128,000 people across the US and Canada, posted revenues of $30.8bn in 2006.