The larger four-finger Kit was certified Fairtrade in January 2010.
The decision commits Nestlé to buy an additional 5,300 tonnes of sustainable cocoa from Fairtrade farmer co-operatives in the Ivory Coast.
That has only become possible now that nine additional farmer co-operatives in the Ivory Coast are able to supply Fairtrade certified cocoa, securing sufficient volumes for the manufacturer.
As Fairtrade co-operatives, the 4,500 new farmers will not only receive a price that covers the costs of sustainable production but also receive an additional premium to invest in their community or business development projects of their choice, such as improving healthcare and schools.
The new co-operatives will also join the Nestlé Cocoa Plan which was launched in 2009. Nestlé has pledged to invest £65m over 10 years on plant science and sustainability initiatives to support small scale cocoa farmers around the world including the Ivory Coast, the world’s largest source of cocoa.
Neil Stephens, managing director of Nestlé Professional UK & Ireland, said: “This step marks a significant milestone in our ongoing commitment to providing a sustainable future for farmers and their families.
“From January, over 7,000 farmers will be supported by the Nestlé Cocoa Plan, who will not only receive training in sustainable farming practices and better plants, but will also benefit from new schools for their communities as part of our pledge to build 40 schools in the next four years.
“This news means that, from January, over a billion Kit Kats will carry the Fairtrade mark and we aim to make the cocoa for all our confectionery brands in the UK and Ireland certified sustainable by the end of 2015.”