The brewer will take over producing, marketing, selling and distributing the beer - previously supplied by Scottish & Newcastle UK - from Nov 1. It said it had set aside "a significant budget" to support the brand.
A "heavyweight" marketing programme is to be unveiled in the coming months.
Brand owner Mahou-San Miguel Group said in a statement: "We are confident that the team at Carlsberg are well placed to unlock San Miguel's potential within the UK off-trade."
Carlsberg said the move is part of its growing commitment to world beers. Earlier this year it added Russia's Baltika, Greek Mythos and Belgian Grimbergen to its portfolio.
Scottish & Newcastle UK, which was taken over by Heineken at the beginning of this year, said customers could expect "business as usual" until Nov 1. It added that no other S&N brands are affected by the deal.