Almost 2,000 Wilko staff, including those at the Worksop distribution centre, will walk out over forced weekend working.
GMB, the union for Wilko workers, has revealed the dates of two planned strikes.
Around 1,800 GMB members at two Wilko distribution centres in Worksop and Magor, Wales will strike from 6am on Friday, October 11, until 5.59am on Saturday, October 12, and from 6am on Monday, October 14, to 5.59am on Tuesday, October 15.
Gary Carter, GMB National Officer, said: “It is sad that it has come to this. We have done everything we can to try to negotiate a reduction in the amount of weekend working, but the offer from management is not acceptable.
“Wilko has always considered itself a family company - yet they’re forcing contracts on staff that will seriously impose on family time and workers’ wellbeing.
“GMB members will stand together and show Wilko management how strongly we feel about these harsh new contracts.”
A Wilko spokesman said: “We’re sorry it has come to this and would like to reassure our customers and team members that we have robust plans in place so they can continue to shop and work with us as normal.
“We’re the last of the major retailers to introduce regular weekend working in our distribution centres as a result of customer demand for seven days a week shopping.
“We want to support our team members in responding to the 24/7 reality of retailing today while also helping them to spend as much time as possible with their families.
“We’ve already given 400 team members an additional weekend off before our peak trading period begins and in a recent meeting with the union we’ve also offered to guarantee 2 in 3 weekends off outside of peak from January 2020 onwards.
“We don’t believe industrial action is in anyone’s best interests at this challenging time for the high street and retail in general. We have always believed the right way to resolve any differences is through listening, talking and working things through together and we encourage the GMB to call off their the strike and join us in finding a way forward which works for both our customers and their members.”