The UK's third largest supermarket, which operates 1,200 stores, said it had taken the decision to reduce its staff numbers in order to make cost savings and reinvest back into areas that "really matter" to consumers, including price and service.
It is the second round of job cuts announced by the retailer this year. In January it axed 500 jobs after reporting its worst Christmas trading for a decade, despite its high-profile Christmas Truce TV ad. Q1 sales also tumbled 2.7%.
The grocer is also making changes to night shifts in some stores, replacing overnight shifts with early morning and evening shifts, and taking fewer deliveries in some stores, which it said would result in improved availability.
Sainsbury's claimed as a result of the changes, existing colleagues would be able to take extra shifts and therefore there would be more staff on hand in stores.
"These are exceptionally difficult decisions to make and we have not taken them lightly," said Roger Burnley, retail and operations director.
"We set out very clearly last year that we have to reflect the changes in when and how our customers are shopping. These proposals will help us maintain and improve customer service by having more colleagues on hand and well-replenished shelves at all times."