Brittain replaces Brid Drohan-Stewart, who is leaving the soft-drinks giant to return to New Zealand.
In his new role, Brittain will report to Jon Woods, general manager of Coca-Cola Great Britain and Ireland.
He will be responsible for the development of the company's marketing strategy in Great Britain and will oversee all aspects of activation, including campaigns for the company's 21 UK brands including Coke, Diet Coke, Coke Zero, Sprite and Fanta.
Brittain joined Coke in 2004 as a brand director before becoming vice president of sparkling for Coca-Cola Canada, and general manager of Coca-Cola Italy.
Drohan-Stewart is leaving her position after just over a year in the role. She replaced Zoe Howorth in April last year, after the former marketing director left to take a year's sabbatical.
The news comes as Coke's chief marketing officer Jonathan Mildenhall is leaving the company amid a reshuffle at the company, to become the chief marketing officer at Airbnb.