The switch by Maltesers, which is the third biggest confectionery brand in the UK, will represent more than a 10% increase in total UK Fairtrade sales, the company claims.
Mars says the move will contribute $1m (£640,000) a year in Fairtrade funds to cocoa farmers to invest in their farms and local communities.
It follows similar switches by its rivals, including Kraft’s Dairy Milk brands and Nestle’s KitKat, which source their cocoa from Fairtrade production methods.
Mars says it intends to buy all of its cocoa from sustainable production sources by 2020. In 2009, sustainably certified cocoa, represented just 1% of total purchases, the Fairtrade Foundation claims.
Fiona Dawson, president of Mars Chocolate UK, says: “Mars is looking to lead the way in enabling certification for the whole cocoa sector, and this agreement with Fairtrade is a significant step in the drive for cocoa sustainability worldwide.”
Mars also says it is investing heavily in Côte d’Ivoire and other major cocoa producing countries over the next 10 years to provide farmers with the training and tools to meet in the increasing demand for cocoa.
Current annual world production of coca is around 3.5 million tonnes and Mars says the chocolate confectionery industry will need at least 4.5 million tonnes by 2020.