Do I file my tax return in ON or BC if my home is in ON but I go to university in BC?

Your principal residence address is Ontario even if you are living in BC for school. As per the Canada Revenue Agency (CRA) Determining an Individual’s Residence Status: Under normal conditions, a person files a tax return for the province in which they are residing on December 31 of the taxation year. Sometimes, a person may be considered to be a resident of a province even if they have temporarily relocated to another province. This could happen if the person was a student in a province where they do not normally reside. A person will be determined to be resident in the province in which they have the most significant residential ties. 

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