Family & Dependents
Both Parents Claimed the Same Child on a Tax Return: What the IRS Does (2026)
The short answer: when both parents claimed child on an IRS return, the IRS flags the duplicate Social Security number. The second e-filed return rejects. If both file on paper, the IRS mails each parent a CP87A notice. If neither backs down, the IRS applies the tiebreaker rules — and the custodial parent usually wins.
⏱ Your deadline: if you got a CP87A notice, respond by the date printed on it — usually within 30 days. If your e-file was rejected and you are entitled to the child, you must paper-file by your normal filing deadline to protect your refund and credits. The IRS generally has 3 years to open an exam on a return.
Why this happened
The IRS lets only one taxpayer claim a given child for the same tax benefits in the same year. When both parents — or a parent and a grandparent, or two ex-spouses — put the same child's Social Security number on their returns, the IRS computer sees a duplicate and stops it.
This almost always happens for one of a few reasons:
- Divorced or separated parents who each believe they have the right to claim the child.
- A misread court order. Many decrees say a parent "may claim" the child, but a state court order does not override federal tax rules by itself.
- An honest mix-up about whose year it was, or a year the parents were supposed to alternate.
- One parent filing fast to get the refund first, before the other could file.
Whatever the reason, getting flagged does not mean you did anything criminal. It means two returns can't both stand, and the IRS has a fixed set of rules to decide which one does.
What happens if you ignore it
Doing nothing doesn't make the conflict go away — it just moves you down an automated path with worse outcomes. Here's the sequence:
- E-file rejection. The second return to use the child's SSN bounces back with an error. Nothing is decided yet — you simply can't e-file with that child.
- CP87A notice. If both parents file (one on paper), the IRS mails each one a CP87A asking them to check whether they were really entitled to the child. It does not name the other person.
- IRS exam (audit). If neither parent amends, the IRS opens an examination and asks both for proof — school records, medical records, custody logs showing where the child lived.
- Disallowed claim. The parent who loses must repay the refund tied to the child, including the Child Tax Credit and Earned Income Tax Credit (EITC), plus interest and possibly a 20% accuracy penalty.
- EITC ban. If the IRS finds the EITC was claimed recklessly, you can be barred from claiming it for 2 years — or 10 years if it finds fraud.
The faster path is almost always to respond, not wait. If you were entitled to the child, responding protects your money. If you weren't, amending early limits the penalties.
Who actually gets to claim the child: the tiebreaker rules
The IRS doesn't go by who filed first or who "needs it more." It uses written tiebreaker rules, explained in the IRS qualifying child rules. When two parents both qualify, the order is:
- The parent the child lived with longer during the year (counted in nights) is the custodial parent and wins.
- If nights are equal, the parent with the higher adjusted gross income (AGI) wins.
This is why "I have a court order" often isn't enough on its own. A divorce decree can say the noncustodial parent gets to claim the child, but for the IRS to honor it, the custodial parent generally must sign Form 8332, Release of Claim to Exemption, and the noncustodial parent must attach it to the return.
One important detail: even with Form 8332, the noncustodial parent only gets the dependent and the Child Tax Credit. The EITC and the head-of-household filing status always stay with the parent the child actually lived with. They cannot be split or signed away.
Your options once both returns are filed
Where you go next depends on whether you were the parent entitled to the child:
- You were entitled to the child. File a correct paper return claiming the child (if e-file rejected), keep your records, and respond to any CP87A by confirming your claim. You don't amend — you defend.
- You were not entitled to the child. File an amended return (Form 1040-X) removing the child as soon as possible. Doing it before the IRS forces the issue keeps penalties lower.
- You're not sure. Count the nights the child spent at each home. The custodial-parent rule decides it, not whose turn you thought it was.
- The other person filed in bad faith or you suspect identity misuse, not just a custody dispute — that's a different problem worth reviewing, similar to when someone filed taxes in your name.
How to respond, step by step
- Confirm you qualify. Use the IRS qualifying child rules: relationship, age, residency (more than half the year), and support. Where did the child sleep most nights?
- If your e-file rejected and you qualify: print, sign, and mail a paper return claiming the child. Don't drop the claim just to make the rejection go away.
- Gather proof now. School, daycare, or medical records, a lease, and any custody calendar that shows where the child lived. You may need it later even if no one asks today.
- If you got a CP87A: follow the instructions on the notice. Confirm your claim if you were right; amend with Form 1040-X if you were wrong.
- If a refund was already disallowed or you now owe: you have options — a payment plan, penalty relief, or audit reconsideration if you can show you were the rightful parent. Don't ignore a balance hoping it clears.
Caught in a "both parents claimed the child" mess?
Send us your rejection notice or CP87A. An experienced tax professional will tell you who the IRS rules favor, what proof you'll need, and how to respond — free, confidential, no pressure.
Both parents claimed the same child: common questions
What happens if both parents claim the same child on taxes?
The IRS computer flags the duplicate Social Security number. If both file electronically, the second return rejects automatically. If both file on paper, the IRS processes both, then mails each parent a CP87A notice asking them to verify the claim. If neither backs down, the IRS opens an exam and applies the tiebreaker rules to decide who keeps the child.
My e-file was rejected because someone already claimed my child — what do I do?
First, make sure you are actually entitled to claim the child under the qualifying child rules. If you are, you cannot e-file with that Social Security number again this season — you have to print, sign, and mail a paper return claiming the child. The IRS will then process both returns and contact both parents to sort out who is correct.
Which parent has the right to claim the child?
By default the custodial parent — the one the child lived with for more nights during the year — has the right to claim the child. The noncustodial parent can only claim the child if the custodial parent signs Form 8332 releasing the exemption. A court order or divorce decree alone does not override the IRS rules unless Form 8332 is attached.
Can both parents claim the same child if they split custody?
Two parents cannot both claim the same child for the same benefits in the same year. One parent claims the child as a dependent. In some cases parents alternate years using Form 8332, but in any single year only one parent gets the dependent, the Child Tax Credit, and the Earned Income Tax Credit for that child.
What is a CP87A notice?
A CP87A is the letter the IRS sends when more than one taxpayer claimed the same dependent. It does not name the other person. It asks you to check whether you were entitled to the claim and to amend your return if you were not. If you were correct, you keep your return as filed and keep your records ready in case the IRS asks for proof.
Will I have to pay back my refund if I claimed the child wrongly?
If the IRS decides you were not entitled to the child, you have to repay the related refund — including the Child Tax Credit and Earned Income Tax Credit — plus interest and possibly a 20% accuracy penalty. Wrongly claiming the EITC can also bar you from claiming it for two years, or ten years if the IRS finds fraud.
This guide is general information, not tax or legal advice for your specific situation. Eligibility for IRS programs depends on individual facts and circumstances; no outcome is guaranteed.