Is that a US thing? I'm up in Canada, and the RSU structure for my employer is an initial grant of $3x, with $x vesting every year for three years. Only when I

Is that a US thing? I'm up in Canada, and the RSU structure for my employer is an initial grant of $3x, with $x vesting every year for three years. Only when I exercise the vested RSUs (flat exchange at fair market value - typically the average stock price over the past week) do I declare them as income, at which point it's taxed as per usual for employment income.