The Basic Rule: Children Under 17 and Your Income Level

You can claim the Child Tax Credit if you have a child under age 17 at the end of the tax year, you claim that child as a dependent on your tax return, and your income falls below a threshold that changes each year. The credit is worth up to $2,000 per child. Your income limit depends on your filing status — it is higher if you file as married filing jointly than if you file as head of household or single.

The income thresholds are set by the IRS each year and adjust for inflation. For the 2023 tax year, the phase-out began at $400,000 for married couples filing jointly and $200,000 for single filers and heads of household. If your income exceeds these amounts, the credit reduces by $50 for each $1,000 (or fraction of $1,000) over the limit.

Your child must be a U.S. citizen, national, or resident alien with a valid Social Security number. You must also be a U.S. citizen, national, or resident alien yourself to claim the credit.

Key Takeaways

  • The Child Tax Credit requires your child to be under 17 at the end of the tax year, claimed as your dependent, and have a valid Social Security number.
  • Your income must be below the IRS threshold for your filing status, which changes annually and is higher for married couples filing jointly.
  • The credit is worth up to $2,000 per child, but reduces if your income exceeds the threshold.
  • You must be a U.S. citizen, national, or resident alien to claim the credit on your tax return.

What "Dependent" Means and How to Prove It

To claim the Child Tax Credit, you must claim the child as a dependent on your tax return. This means the child lived with you for more than half the year (with limited exceptions for temporary absences like school or medical care), you provided more than half their financial support during the year, and the child is related to you or lived with you as a member of your household for the entire year.

You do not need to submit separate proof to the IRS when you file — the dependent claim itself is your declaration. However, you should keep records showing the child lived with you and that you paid for their housing, food, medical care, education, and other support. If the IRS questions your return, you will need to show these records: rent or mortgage statements, utility bills, school enrollment records, medical bills, or receipts for clothing and supplies.

If two parents share custody, only one can claim the child as a dependent in a given year. Usually this is the parent with primary custody, but parents can agree otherwise. The parent who claims the child gets the credit.

Age and Relationship Requirements

The child must be under 17 on December 31 of the tax year. A child who turns 17 on that date does not may have access to. The child must also be your son, daughter, stepchild, foster child, sibling, or a descendant of any of these (such as a grandchild or niece). Cousins do not count.

Foster children must have been placed with you by an authorized placement agency or court order. If you adopted a child, they count as your child for the credit. If you are the legal guardian but have not adopted, the child does not may have access to unless they are a relative.

Income Limits and How They Work

The IRS sets income thresholds each year. Your income is measured by your modified adjusted gross income (MAGI), which is usually your adjusted gross income (AGI) from your tax return. If your MAGI is at or below the threshold for your filing status, you can claim the full $2,000 credit per child.

If your MAGI exceeds the threshold, the credit reduces by $50 for each $1,000 over the limit, rounded up. For example, if you file as single with MAGI of $201,500 and the threshold is $200,000, you are $1,500 over the limit. That rounds up to 2 increments of $1,000, so your credit reduces by $100 (2 × $50), leaving you with $1,900 per child instead of $2,000.

The thresholds vary by filing status. Married couples filing jointly have the highest threshold, followed by heads of household, then single filers. Married couples filing separately have the lowest threshold and are rarely able to claim the credit.

Social Security Number Requirements

Your child must have a valid Social Security number (SSN) issued by the Social Security Administration. A number issued for work purposes, an Individual Taxpayer Identification Number (ITIN), or a number that has not yet been issued does not count. You must enter your child's SSN on your tax return to claim the credit.

If your child does not yet have an SSN, you can request one from the Social Security Administration before you file your tax return. The process usually takes two to four weeks. You can file your return once the SSN is issued, or you can wait until you have it in hand before filing.

Residency and Citizenship Status

Both you and your child must be U.S. citizens, nationals, or resident aliens. A resident alien is someone who has a green card or meets the substantial presence test (generally, being in the U.S. for at least 31 days in the current year and 183 days over a three-year period).

If you are a nonresident alien, you cannot claim the Child Tax Credit, even if your child is a U.S. citizen. If your child is a nonresident alien, you cannot claim the credit for that child. Visa holders (such as H-1B or L-1 visa holders) may may have access to as resident aliens if they meet the substantial presence test.

What Happens If You Claim Someone Else's Child

Only one person can claim a child as a dependent in a given tax year. If two people claim the same child, the IRS will disallow one of the claims and may assess penalties. If you and another parent share custody, you must decide who will claim the child each year, or you can alternate years.

If you claim a child and later discover you were not may have access to to do so — for example, because the child's other parent already claimed them — you should file an amended return (Form 1040-X) to correct the error. The sooner you correct it, the lower the risk of penalties and interest.

Frequently Asked Questions

Can I claim the credit if my child was born late in the year?

Yes, if your child was born before January 1 of the following year. The child's age is determined on December 31 of the tax year. A child born on December 31 counts as under 17 for that year's credit.

What if my child has no Social Security number yet?

You must obtain a Social Security number before you can claim the credit. Contact the Social Security Administration to request one. The process typically takes two to four weeks. You can file your return once the number is issued.

Can I claim the credit if I do not have custody?

No. You must claim the child as a dependent, which requires the child to have lived with you for more than half the year and you to have provided more than half their support. If you do not meet these requirements, you cannot claim the credit, even if you are the child's parent.

Does my income include child support I receive?

No. Child support received is not counted as income for tax purposes. However, other income — wages, self-employment income, investment income, and some benefits — does count toward your MAGI and may reduce or eliminate your credit if it exceeds the threshold.

Can I claim the credit if I file as married filing separately?

Married couples filing separately have a very low income threshold ($0 for the 2023 tax year), which means the credit phases out immediately. Filing jointly gives you a much higher threshold and is almost always the better option if you are married.