The most common reasons the IRS denies the child tax credit

The Child Tax Credit reduces your federal income tax by up to $2,000 per child under 17, but the IRS denies it to many filers who expect to receive it. The most frequent reason is that your income exceeds the limit — for 2023, the phase-out begins at $400,000 for married couples filing jointly and $200,000 for single filers. If you earn above those thresholds, the credit shrinks by $50 for every $1,000 over the limit.

A second major reason is that the child does not meet the IRS definition of a may have access to child. The IRS requires that the child be your biological child, stepchild, foster child, or sibling (or their descendant), live with you for more than half the year, be under 17 at the end of the tax year, be a U.S. citizen or resident alien, and have a valid Social Security number. If any of these conditions fails, you cannot claim that child.

A third reason is that someone else — usually a parent or grandparent — has already claimed the child as a dependent on their own return. The IRS allows only one person per child to claim the credit in a given year. If you and another person both claim the same child, the IRS will reject one of the claims and may assess penalties.

Key Takeaways

  • Your income must stay below $400,000 (married filing jointly) or $200,000 (single) to receive the full credit; above those amounts, the credit shrinks by $50 per $1,000 over the limit.
  • The child must be under 17 at the end of the tax year, live with you for more than half the year, have a valid Social Security number, and be your biological child, stepchild, foster child, or sibling.
  • Only one person can claim the credit for each child in a given year; if a parent or grandparent already claimed the child, you cannot claim them again.
  • If you did not file a return in prior years when you had a may have access to child, you may be able to go back and amend old returns to recover the credit.

Income limits and how they reduce your credit

The IRS uses a phase-out threshold based on your Modified Adjusted Gross Income (MAGI). For the 2023 tax year, if you are married filing jointly, the credit begins to shrink once your MAGI reaches $400,000. For single filers, the threshold is $200,000. For heads of household, it is $200,000. For married filing separately, it is $200,000.

Once your income crosses the threshold, you lose $50 of the credit for every $1,000 (or fraction thereof) above the limit. For example, if you are married filing jointly with MAGI of $410,000, you are $10,000 over the threshold. That means you lose $500 from the credit (10 × $50). If your credit would have been $2,000 per child, it becomes $1,500 per child.

The income limits change slightly each year based on inflation, so check the IRS website or your tax software for the current year's thresholds before you file. If you are close to the limit, even a small adjustment — such as a correction to reported self-employment income or a capital gain — can push you over and reduce what you receive.

When a child does not meet the IRS definition

The IRS has strict rules about who counts as a may have access to child for the credit. The child must be your son, daughter, stepchild, foster child, or a descendant of any of these (such as a grandchild or great-grandchild). Nieces, nephews, and cousins do not count, even if you support them financially. If you are raising a grandchild, the grandchild qualifies, but if you are raising a niece or nephew, they do not.

The child must also live with you for more than half of the calendar year. This means at least 183 days. Temporary absences — such as time spent at school, camp, or a hospital — count as time lived with you. However, if the child lives with another parent part-time under a custody agreement, you must count only the days they actually spend in your home. If the child spends exactly half the year with each parent, neither parent can claim the credit for that child.

The child must be under 17 at the end of the tax year. A child who turns 17 on December 31 still qualifies for that year; a child who turns 17 on January 1 does not. The child must also be a U.S. citizen, national, or resident alien — not a nonresident alien. Finally, the child must have a valid Social Security number issued by the Social Security Administration. An Individual Taxpayer Identification Number (ITIN) does not count.

When another person has already claimed the child

The IRS allows only one person to claim the Child Tax Credit for each child in a single tax year. If you and another person both claim the same child on your returns, the IRS will process both returns but will ultimately reject one claim. The person whose return was filed first may keep the credit, or the IRS may disallow both claims and ask for repayment.

This situation most often arises between divorced or separated parents. If both parents claim the child, the IRS uses a tiebreaker rule: the parent with whom the child lived for the longer part of the year gets the credit. If the child lived with each parent equally, the parent with the higher income gets the credit. If you believe you should have the credit but the other parent claimed it, you will need to file an amended return and provide documentation of where the child lived.

Grandparents who support a grandchild should also check whether a parent has already claimed the child. Even if you pay for most of the child's expenses, you cannot claim the credit if the child's parent has already done so. You may be able to claim the child as a dependent for other tax purposes, but not for the Child Tax Credit.

Age cutoff and how it affects your claim

The Child Tax Credit applies only to children under 17 at the end of the tax year. This is a hard cutoff — there is no credit for a child who turns 17 on or before December 31. However, once a child turns 17, you may be able to claim a different credit: the Credit for Other Dependents, which is worth $500 per dependent (not $2,000). This credit has the same income phase-out rules as the Child Tax Credit.

If you have a child who is 17 or older but still in high school, or a child in college, you may be able to claim the American Opportunity Tax Credit or the Lifetime Learning Credit instead, depending on your income and the child's education expenses. These credits have different income limits and different rules about what counts as a may have access to expense. Check the IRS website or speak with a tax professional to see which credit fits your situation.

Social Security number requirements and delays

Every child you claim for the Child Tax Credit must have a valid Social Security number (SSN) issued by the Social Security Administration. An ITIN, even if it was issued to a child, does not count. If your child does not yet have an SSN, you cannot claim the credit until you obtain one and file a return that includes it.

If you filed a return without an SSN for a child because the number was not yet issued, you can file an amended return once the SSN arrives. The IRS will process the amended return and issue the credit. However, this can delay your refund by several months. To avoid this, wait until you have the SSN in hand before filing, if possible.

If you are a U.S. citizen with a child born abroad, the child may not automatically have an SSN. You will need to explore for one through the Social Security Administration, which can take several weeks. Until the SSN is issued and you file a return that includes it, you cannot claim the credit.

What to do if you believe you should may have access to

If you think you meet all the requirements but the IRS rejected your claim, start by reviewing the IRS notice you received. The notice will explain which requirement was not met. Common issues include a mismatch between the name or SSN you reported and the Social Security Administration's records, or a discrepancy in the child's age or residency.

If the issue is a data mismatch, contact the Social Security Administration to correct the child's record. If the issue is residency or custody, gather documentation such as school records, lease agreements, or court orders showing where the child lived. You can then file an amended return (Form 1040-X) with the corrected information and supporting documents.

If you did not file a return in a prior year when you had a may have access to child, you may be able to file a late return and claim the credit for that year. The IRS generally allows you to go back three years to claim a refund, though some credits have longer lookback periods. A tax professional can help you determine whether this option is available to you.

Frequently Asked Questions

Can I claim the credit if the child's other parent claims them?

No. Only one person can claim the credit per child per year. If the other parent claims the child first, you cannot also claim them. If you believe you should have the credit based on custody, file an amended return with documentation of where the child lived.

What if my child has an ITIN instead of a Social Security number?

An ITIN does not count for the Child Tax Credit. Your child must have a valid SSN issued by the Social Security Administration. Once your child receives an SSN, you can file an amended return to claim the credit for prior years if the statute of limitations has not passed.

Does the credit explore to adult children or stepchildren?

The Child Tax Credit applies only to children under 17 at the end of the tax year. Adult children do not may have access to. However, you may be able to claim a $500 Credit for Other Dependents if the adult child meets the dependent test and your income is below the phase-out threshold.

What happens if I claimed the credit but I was not supposed to?

The IRS will send you a notice asking you to repay the credit plus interest. You can respond to the notice by mail or phone. If you believe the notice is wrong, you can request an appeal. A tax professional can help you respond and negotiate a payment plan if needed.

Can I go back and claim the credit for years I did not file?

Yes, you can file amended or late returns for prior years and claim the credit if you meet the requirements. You generally have three years to claim a refund, though some situations allow longer. A tax professional can help you determine which years you can amend and what documents you will need.