Canadian businesses using the Square reader can now accept American Express payments to go along with Visa and MasterCard.

Canada has more than 1 million small businesses, Square said in a news release, and 2.7 million people who are self-employed.

"Small businesses are a huge part of not only the Canadian economy, but the Canadian identity," Jennifer Hawkins, vice president and general manager of merchant services, American Express Canada, said in the news release. "We've been working hard to identify more ways to support small merchants, and American Express acceptance with Square is a great next step.

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