Usually, the custodial parent gets to claim any qualifying children as dependents.
However, the IRS doesn’t use the same definition of custodial parent that family court does.
In certain cases, your divorce decree might say that one parent has custody, but the IRS determines that the other parent should be able to claim the child for taxes.
For tax purposes, the custodial parent is usually the parent the child lives with the most nights. If the child lived with each parent for an equal number of nights, the custodial parent is the parent with the higher adjusted gross income (AGI).
If you feel that you should be able to claim the dependent, you’ll need to print and mail your return. You won’t be able to e-file. The IRS won’t allow two different people to e-file using the same dependent Social Security number (SSN).
The IRS will then send a letter to both of you to determine who gets to claim the exemption for the child. If you can’t agree on who claims the child, the tie-breaker rules apply. Under the tie-breaker rules, the child is a qualifying child only for:
- Whoever the child lived with the longest during the tax year
- The parent with the highest AGI if the child lived with each parent for the same amount of time during the year
- The person with the highest AGI if no parent can claim the child as a qualifying child
- A person with an AGI higher than any parent if the parent can claim the child as a qualifying child but doesn’t
