Are they withholding us taxes or things like social security or Medicare? Or are they withholding the Canadian equivalents? Contractor or on payroll employee?

Are they withholding us taxes or things like social security or Medicare? Or are they withholding the Canadian equivalents? Contractor or on payroll employee? A us-ian files taxes to the us every year but I did not think others outside the us did so. But you would have to file to recover any taxes withheld or consider them as foreign taxes paid when filing in Canada. Canadian taxes are higher than the us so you should not end up paying the us anything.