He has replaced Brian Metcalfe of DBC Foodservice, who steps down from the position ahead of his retirement.
Blakemore Wholesale is part of AF Blakemore, Landmark Wholesale's biggest member. The wholesale division includes cash & carry, foodservice and fresh foods.
Wilcox, who has worked at Blakemore for 25 years, said he aimed to continue helping Landmark to prosper and develop. Current initiatives include the rollout of the buying group's Lifestyle Express Evolution Programme and the ongoing development of own-label ranges.
"Sam has great ability to plan strategically," said Landmark Wholesale MD Martin Williams.