The measure announced last week is expected to help revive the economy after the pandemic caused unprecedented job losses in March and April.
All retail stores with street entry will be allowed to open for both curbside pickup and delivery – a decision by Premier Doug Ford will allow thousands of people to return to work.
Friday, the government authorized the complete reopening of garden centers and nurseries, and hardware stores could do the same on Saturday.
According to data released Friday by Statistics Canada, 689,200 Ontarians lost their jobs in April, in addition to the 403,000 who the agency said were lost in March.
The province reported 294 new cases of COVID-19 on Sunday, a jump of just 1.5% from the previous day.
The total number of confirmed cases of COVID-19 now stands at 20,238, with a death toll of 1,634.
Ford also announced over the weekend that provincial parks will reopen on Monday, although beaches, campgrounds and playgrounds will remain closed and physical distance must be maintained.