Headquartered in Mississauga, Ontario, it was founded on March 17, 1994, with the purchase of the Woolco Canada chain from the F. W. Woolworth Company.

Based on the success of the US format, Walmart Canada has focused on expanding Supercentres from new or converted locations, offering groceries which puts them in the same market as supermarket chains such as Loblaws, Real Canadian Superstore, Real Atlantic Superstore, Your Independent Grocer, No Frills, Metro, Sobeys, Foodland, Thrifty Foods, Safeway, Save-On-Foods, Country Grocer, Fairway Markets, Quality Foods, Co-op and others.

[13] Pilozzi, who retired in 2008, has proclaimed that he and "his management team took a limping chain and turned it into the Walmart powerhouse that became a game-changer on the Canadian business scene.

Retailers changed, Canadian manufacturers faced demands and volumes they had not seen before, real estate transitioned from enclosed malls to big-box plazas".

[14] Reflecting on the 1994 deal in 2013, a Walmart Canada spokesman was quoted as saying "Even though Woolco had seen better days and was struggling, there was still an enormous amount of talent in that company.

[21] In 2015, Walmart Canada disabled their online photo site,[22] blaming a third party vendor, believed to be PNI Digital Media.

In common with other potential victims[24] there was no confirmation or denial about whether hackers had stolen customer photographs as well as data and payment information.

[28] Since 1994, many of the shopping centres in which Walmart is located have been developed by SmartCentres (originally known as First Pro), a real estate company founded by Mitchell Goldhar.

[32][33] This was part of Walmart Canada's decision to shift focus towards Supercenter stores, but some industry observers suggested that the operation was struggling to compete with Costco and the non-membership Real Canadian Superstore (known as Maxi & Cie in Quebec).

Councillor Anne Roberts stated that her opposition was due to potential traffic and congestion that the store would bring to south Vancouver, although she later remarked "I'm not a fan of Wal-Mart, and I've always been concerned about their labour practices, about getting goods from sweatshops".

[15] Walmart Canada launched the "Urban 90" format in 2012, a set of smaller Supercentres averaging 90,000 sq ft (8,400 m2).

[42] The first Supercentre in Vancouver, British Columbia opened in January 2009 in a former Costco/Price Club location, which moved to a new larger site nearby in Burnaby.

Many Walmart Supercenters also feature a garden centre, pet shop, pharmacy, optical centre, one-hour photo processing lab, portrait studio, a clinic and numerous alcove shops, such as cellular phone stores, hair and nail salons, video rental stores (including Redbox rental kiosks), local bank branches, and fast food outlets, Walmart Canada Bank launched its application for banking license in 2008 to compete with similar stores in Canada such as Loblaw.

[48] On August 15, 2013, the Supreme Court of Canada upheld the decision for Weyburn employees to dissolve their union, as they had voted 51–5 to decertify United Food and Commercial Workers (UHCW) as their representative.

[48] Walmart closed their Saguenay store in April 2005 after workers unionized and days before contract settlement by binding arbitration, putting 190 employees out of work.

[51] In September 2005, the Quebec Labour Board ruled that the closing of a Walmart store amounted to a reprisal against unionized workers and has ordered additional hearings on possible compensation for the employees, though it offered no details.

[48] The case went to the Supreme Court of Canada in 2014, which ruled that Walmart had violated the Quebec Labour Code and fined the company.