Co-op announced the offer to its 6.5 million members who supported the business during the cyberattack as its 2,300 food stores returned to usual trading.
The offer runs from 18 to 24 June and can be used by members, including new ones, once.
Co-op managing director of food Matt Hood said: “I’m very proud that, thanks to the work of our colleagues, we are very near to making a full and complete recovery from the recent cyberattack on our Co-op, and I’m delighted to see our stores looking back to normal and being able to serve our shoppers and communities.
“We are so grateful to our member owners for their support and patience with us during what was a very difficult time and hope this gesture of appreciation goes a little way to showing them our thanks, with more value rewards to come over the summer.”