The turnover of co-operative societies in the UK rose 5.4% last year to £28.9bn, new data from Co-operatives UK has revealed.

The performance was boosted by The Co-operative Group's acquisition of Somerfield, allowing the society to cement its position as the UK's largest co-op society with a turnover of £9.1bn. John Lewis Partnership, the owner of Waitrose, was once again the second largest co-op, with a turnover of £6.7bn last year. Midlands Co-op, Midcounties Co-op and dairy co-op First Link completed the top five.

Consumers liked the way co-op societies operated, but the sector should not become complacent, said Ben Reid, chairman of Co-operatives UK and CEO of Midcounties Co-op. "Maintaining our velocity will not be easy," he said. "Co-operatives offer a better way of doing business, so we must keep pushing to get our message across to more people."