For sons tax return., separated after December 31,24. spouse not communicating (in family court). How can we complete his return, without knowing his spouses income?

If you do not have the exact amount, the Canada Revenue Agency (CRA) suggests that you do your best to estimate the amount.  It is important to enter it. The CRA knows it can be difficult but even an estimate helps them calculate certain credits and deductions. They will be able to match the information with each of the files that they already have. When they see the "separated" status they expect there to be estimates.

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