It was broken up in the mid-1980s, with key locations and the rights to the brand sold to The Great Atlantic & Pacific Tea Company (A&P), which restricted the chain to the Greater Toronto Area.

[4] The chain also expanded beyond Toronto to other parts of Ontario, Quebec, Alberta, Manitoba,[5] Saskatchewan and Atlantic Canada.

In Western Canada, Dominion stores were closed, leaving many suburban shopping malls scrambling to fill large, now-vacant sections.

This event, coupled with the subsequent collapse of several department store chains, sparked a wave of mall renovations in many parts of the country.

Much of the remainder of the chain in eastern and central Canada was ultimately acquired by Loblaw Companies, through several unrelated transactions: In 1985, during the chain's breakup, the Argus-controlled Dominion Stores Ltd.—renamed Domgroup Ltd. in April 1986—withdrew $37.9 million from its defined benefit pension plan for Canadian employees.

[7] Most of the remaining "old" Dominion stores ultimately closed in early 1986, ahead of A&P gaining exclusive rights to the name on April 30.

[7] The territory of Dominion stores was approximately the following: Toronto; York Region, excluding Stouffville; Mississauga and Oakville; and Pickering and Ajax.

Metro, which had operated solely in Quebec and the Ottawa area, acquired A&P Canada from the U.S.-based parent company effective August 15, 2005.