Thanks for your question. When you don’t know your spouse’s income and can’t find out through reasonable means, the CRA recommends that you enter your best estimate.

• The CRA will assess you and your spouse’s (or former spouse’s) returns together to ensure that credits and deductions were correctly applied between you. If there’s any inaccuracy or mismatch, they’ll reassess your returns.
• Tip: You may want to save your tax refund (if any) until you receive your Notice of Assessment or Reassessment in case some or all of it needs to be repaid.

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