Obviously you do not make over 200k.  The provincial taxes are on top of the 33% marginal rate.   It is over 50% in some provinces.   You also loose all the child benefits.   If you want to work harder and go from 300k/year to 400k/year you will lose half the extra amount.  It may not be worth it for some resource workers, construction managers, etc to leave their family to put in extra weeks of work.