The stores, both owned by Loblaws, posted on their Facebook pages Saturday morning to announce the new rules.
“We appreciate your support as we work together to stop the spread of COVID-19,” the company said.
There are real Canadian supermarkets in Kelowna, West Kelowna, Penticton, Vernon and Kamloops, while Oliver and Salmon Arm have No Frills locations.
The new changes come after a COVID-19 outbreak was declared last week at a Loblaws warehouse in Fraser Health Region, where nine employees contracted the disease. The outbreak did not occur in a store and it is not clear whether the rule change is related.
Extra Foods and Shoppers Drug Mart are also owned by Loblaws, but these establishments have not made any announcements regarding the masks.
Walmart implemented a mandatory mask policy earlier this month.