More than 3,700 Sainsbury’s workers, represented by law firm Leigh Day, have brought equal value claims against the company arguing that their work is as demanding as distribution centre roles.

Comparability is the first stage in a three-step legal process for equal pay claims. Sainsbury’s will now have to show that the roles are not of equal value or that there is a genuine reason for the pay difference which is not based on gender.

The difference in hourly pay for shop floor workers and those in a distribution centre can range between £1.50 to £4 an hour, which could mean a disparity in pay of many thousands of pounds.

This concession by Sainsbury’s is the most recent in a series of comparability milestones for equal pay claims against supermarkets in the UK. In June the Court of Justice of the European Union (CJEU) ruled employees working in Tesco stores could compare their roles to colleagues working in distribution centres for the purpose of equal pay.

The court ruled that the ‘single source’ test applies to businesses in the UK. This means a worker can compare their role with somebody working in a different establishment if a ‘single source’ has the power to correct the difference in pay.

A similar row is ongoing at Asda. In March the Supreme Court upheld an earlier court ruling that means shop floor staff at Asda (mostly women) can be compared to workers in the distribution centre (mostly men) for the purposes of their equal pay claim.

Leigh Day also represents clients from Morrisons and the Co-op in similar equal pay cases.

Mike Keenan, Leigh Day employment solicitor, said: “This is a huge milestone for Sainsbury’s shop floor workers and truly something to celebrate. Now that Sainsbury’s finally agrees shop floor workers compare their roles to workers in distribution centres, we can focus on what’s at the heart of these claims: whether the work is of equal value. Leigh Day believes it is and we’re confident that the employment tribunal will agree.”