The win, worth £2.5m according to the most recent Nielsen Media Research figures, strengthens CHI's position on the Britvic roster. The agency already handles the company's Tango, Aqua Libra, Amé, Fountain Head and Pennine Spring Water brands.
BBH won J2O in April 2004 as part of a Britvic roster reshuffle that saw Barrett Cernis axed and its premium carbonates account split between BBH and CHI.
BBH remains on the Britvic roster with the Robinsons drinks range, which it picked up in July 2003.
CHI's appointment comes as Britvic reports a 9% slump in sales of its carbonated drinks. The company blamed the fall on an unexpected decline in demand for full-sugar carbonated drinks following the cold spring and late Easter.
The fall led to a 32% drop in first-half earnings, although it was softened by news that Britvic's still-drinks business saw growth of 9%. This was driven by strong sales of the J2O, Fruit Shoot and Robinsons brands.
Britvic awarded CHI the Tango account in February 2002. It was previously held by United London.
CHI declined to comment. Britvic did not return calls as Campaign went to press.
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