If your son still has most of his possessions at home and has not completely moved into his own apartment to stay in Quebec after university and is still dependent on you, then his address is still the same as yours for tax purposes. As per Canada Revenue Agency (CRA), an individual is considered to be resident in the province where he or she has significant residential ties. An individual who is resident in more than one province on December 31 of a particular tax year will be considered to be resident only in the province in which the individual has the most significant residential ties, for purposes of computing his or her provincial tax payable.
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