The maker of biscuit brands such as Wagon Wheels, Maryland Cookies and Jammie Dodgers, will receive over 12,000 metric tonnes of chocolate and compound to Burton’s every year.
Barry Callebaut said it will also acquire Burton’s chocolate manufacturing assets in Wirral, Merseyside.
Through the deal, the chocolate maker will expand its manufacturing capacity in the UK which is seen as a key growth area for the firm.
The Swiss company said it will take on the 48 staff currently employed at the facility and it will continue to make chocolate at the site.
The deal is expected to close by the end of 2018.
Nick Field, chief executive of Burton's Food, said: "Barry Callebaut shares our passion and motivation for baking the best quality products for our customers and consumers.
"This new partnership, with their larger network and enhanced capabilities, directly supports our intent and commitment to maintain and enhance our industry-leading chocolate biscuit offering."
Barry Callebaut's chief executive, Antoine de Saint-Affrique, added: "This transaction is an excellent example of the power of long-term partnerships and outsourcing.
"It is also a clear sign of our commitment to support the growth of our business in the UK market."