There are no disadvantages. The spouse or common-law partner amount is a non-refundable tax credit meant to help families living in the same dwelling where one spouse is financially responsible for the other spouse.
You can claim this amount for the entire year, even if you met the eligibility requirements for only part of the year, if:
The spouse or common-law partner amount is automatically calculated in TurboTax based on your spouse/partner's net income, which means that you can't edit this amount in your return. You may only choose whether to claim or not claim the amount altogether.
For additional information please see our TurboTax FAQ What is the spouse or common-law partner amount?
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