Hi....I'm from the U.S., so no tests required as long as I had my COVID VACCINE card that they scanned upon my check in.  None at embarkation, and none at disembarkation.   Here's a link that makes it sound like they'll test, at least children, at no charge.  Not sure about adults in Canada.  But, check it out.  Probably not a bad idea to call Celebrity directly, too.    https://www.celebritycruises.com/health-and-safety
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