The Canada Revenue Agency limits the expense allowed based on:
TurboTax automatically applies these limits and assigns child care expenses to the lower-earning spouse.
As per our TurboTax article: Family Tax Deductions: What Can I Claim?
As a Canadian taxpayer, you can claim up to 2/3rds of your earned income, to a certain maximum amount per child’s age. You can find this amount in the T778 form.
The deduction must be claimed by the spouse/common-law partner with the lower income. You will not qualify for this deduction if one of the parents is not working, studying, or if they are receiving Employment Insurance (EI). EI qualifies as income only for single parents. The higher income partner can claim this amount if the lower-income partner is enrolled in school, sick, confined in prison, incapable of caring for the child due to infirmity or disability. You will need the receipt from your child care provider to be able to claim this amount.
To review and confirm your child care expense deduction on line 21400:
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