Notice CP87A: IRS Notice CP87A — Someone Else Claimed Your Child
Notice CP87A is the IRS's way of telling you there's a conflict: someone else filed a tax return claiming the same dependent you claimed. The IRS can't give the credit to both parties — so it's asking you to prove your claim is the legitimate one. This situation is more common than most people realize, especially after divorces, separations, or estrangements from family members.
What Triggers CP87A
When two returns claim the same Social Security number for a dependent, the IRS's automated system flags the conflict. The first return processed typically gets the credit — and the second filer receives CP87A asking them to respond with documentation. It doesn't mean you did anything wrong. It means someone else did too, and the IRS needs to sort it out.
Who Gets the Exemption
Under the IRS tiebreaker rules at IRC § 152(c)(4), if both claimants are parents, the parent with whom the child lived for the greater number of nights during the year wins. If time is exactly equal, the parent with the higher adjusted gross income gets the exemption. Court orders don't override these federal rules automatically — you have to follow the proper IRS process.
Your 3-Step Action Checklist
Prove 50.1% residency. Gather school records, medical records, and any other documentation that shows the child lived primarily with you.
Gather identification documents. Birth certificates, custody agreements, and school enrollment records all help establish the child's relationship and living situation.
Respond within the deadline. The CP87A response window is strict. Submit your documentation to the address on the notice via Certified Mail.
When It Escalates
If both parties respond and the IRS can't resolve the conflict through documentation, it may refer the case to examination (audit). At that stage, having an attorney represent you is critical — the other party may be a former partner who is motivated to fight.
We handle dependent conflict cases regularly and know exactly what documentation the IRS responds to. Call us before responding on your own.