The group was forced to shut down parts of its IT systems after discovering the hack, during which all of its 6.5 million members had their data stolen.
Names, addresses and contact information were accessed by hackers during the attack. However, no financial information or transaction data was stolen.
Co-op subsequently faced gaps on the shelves of its grocery stores, with revenues down £206 million in the six months to 5 July 2025.
This translated to the firm suffering a loss of £50 million.
“We believe the hit to the half year is £80m, we believe the hit for the full year is £120m and that’s inclusive of any [insurance] recovery," chief financial officer Rachel Izzard, told Reuters.
Meanwhile, the group’s chief executive Shirine Khoury-Haq said: “The cyber-attack highlighted many of our strengths. But more importantly, it also highlighted areas we need to focus on – particularly in our food business.
“We’ve already started on this journey, refining our member and customer proposition, making structural changes to our business, and setting our Co-op up for long-term success.”
On 10 July, the National Crime Agency announced that two males aged 19, another aged 17, and a 20-year-old female had been arrested in relation to the attacks on three retailers, including the Co-op.
The four young people were apprehended at their home addresses in the West Midlands and London respectively on suspicion of Computer Misuse Act offences, blackmail, money laundering and participating in the activities of an organised crime group.
Speaking about the data loss, Khoury-Haq said she was “devastated that information was taken”.
“I’m also devastated by the impact that it took on our colleagues as well as they tried to contain all of this,” Khoury-Haq added.
“We know a lot of that information is out there anyway, but people will be worried and all members should be concerned.”
Co-op members are able to access discounts in store and vote on motions at the group’s AGM. In May, 73% of members backed a motion that called for the retailer to boycott all Israeli goods in response to the genocide in Gaza, with the boycott confirmed by Co-op a month later.
According to new data analysis, approximately 327,000 Palestinians have now died as a result of the onslaught.
