For the 2025 tax year, if your dependent turned 18 in December, you will not be eligible to claim the Child Tax Credit (CTC) or the Additional Child Tax Credit (ACTC) for that child. The IRS requires that a qualifying child must be under age 17 at the end of the tax year to be eligible for the CTC. Since your child turned 18 during December 2025, they no longer meet the age requirement for the CTC.
Eligibility for Child Tax Credit (CTC)
- Age Requirement: The child must be under age 17 at the end of the tax year (i.e., before December 31, 2025).
- Dependent Status: The child must be claimed as a dependent on your return.
- Citizenship: The child must be a U.S. citizen, U.S. national, or U.S. resident alien.
If your child is still a dependent and meets all other criteria (such as citizenship and TIN requirements), you may be eligible to claim the Credit for Other Dependents (ODC) instead. The ODC is available for dependents who do not qualify for the CTC, including children who are 17 or older at the end of the year.
Claiming the Credit for Other Dependents (ODC)
- Check the “Credit for other dependents” box in row (7) of the Dependents section on Form 1040 or 1040-SR.
- The dependent must have an SSN, ITIN, or ATIN issued on or before the due date of your return (including extensions).
- You cannot use the same child to claim both the CTC and ODC.
Source:
Schedule 8812 Instructions (2025)
Disclaimer: Always verify eligibility and requirements with the current IRS forms and instructions, or consult a tax professional for personalized advice.