Who qualifies as a dependent—Can I claim my daughter’s significant other and his child as dependents?

Maybe.

To claim your child’s significant other, he or she must meet these requirements for a qualifying relative:

• The person must not qualify as somebody else’s qualifying child.
• The person must live with you the entire year (365 days) .
• The person must have earned less than $4,150.
• You must provide more than half of the person’s support for the year.

Any dependent must not file a joint return unless he or she is only filing to claim a refund. This applies to qualifying relatives and qualifying children. Also, there must be no tax liability for either the dependent or the dependent’s spouse if they would have filed separate returns.

You might be able to claim the child of your daughter’s significant other. To do so:

• The child must be a considered a qualifying child or relative using the rules above.
• The child must not qualify as the significant other’s child. This is true unless your child’s significant other isn’t required to file a return. So, he wouldn’t file a return except to receive a refund of taxes withheld and wouldn’t claim the child on that return.
• The child must not qualify as any other taxpayer’s qualifying child.
• Both your daughter’s significant other and his child must live with you all year.
• You must provide more than half of the support to both the significant other and his child.
• They both must make less than the personal exemption amount of $4,150.