Hartlepool-based Camerons Brewery has won a five-year deal to contract brew for Carlsberg.
Camerons, which has 85 staff at its Lion Brewery site, is to brew Tetley's keg Milds and Imperial beers.
Brewing will move across to Cameron from Tetley's Brewery in Leeds in mid-2011.
Tetley's brewery director Andy Hume said: "We are delighted to have found a quality partner to brew Tetley's keg Mild beers and Imperial.
"We are especially pleased to have come to this agreement with Camerons, which is based in a real heartland for Tetley's Imperial."
Camerons boss Chris Soley said: "We are delighted to be working in partnership with Carlsberg UK to contract brew Tetley's keg Milds and Imperial at the Lion Brewery, Hartlepool.
"This partnership allows Carlsberg UK to continue to brew three keg beers which are very popular in this part of the country and this landmark deal adds another global brewer to our portfolio of contract customers.
"Camerons has invested a substantial amount of finance in developing the site and increasing the brewing capacity as well as significant resources in adopting world class manufacturing techniques and standards."