The vote to end their union affiliation came on a 51-5 vote this week, the Canadian Broadcasting Corp. reported Friday.
The union had been the Walmart workers' bargaining agent since 2008 but never negotiated a contract with the U.S. discount retailer, the CBC said.
Union officials contended the decertification process was unfair but Canada's Supreme Court dismissed the union's request that it take up the matter, clearing the way for the vote.
Workers at two other Canadian Walmarts had voted to unionize in the past, but Walmart closed one of them, in Jonquiere, Quebec, and employees at the St. Hyacinthe, Quebec, store later voted to decertify, the CBC said.
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