The Leith Agency adds the Light business to its existing Coors Brewers accounts for Worthington's, Caffrey's and Reef.
It is understood that Leith won the business after a pitch against St Luke's. Coors Light uses the FCB network to handle its global advertising account and, in the UK, Banks Hoggins O'Shea/FCB has run test campaigns in Ireland and Scotland.
It is understood that J Walter Thompson and Soul were also initially shortlisted for the brand, which has always had a low profile in the UK where distribution has been limited.
The agency has been with helping Coors to raise the profile of its Light brand and strengthen its overall position in the UK market.
The review follows Coors' $1.7bn (£1.1bn) acquisition of the Carling division of Bass Brewers from Interbrew in 2000. The deal, which included brands such as Caffrey's and Worthington's, gave Coors control of nearly 20% of the UK beer market.
The Coors Brewers portfolio is split between Leith's Edinburgh and London offices. Grolsch, Worthington's and Caffrey's are run from Scotland, while Carling and Reef are handled at Leith London.
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