My oldest child turns 18 in the first half of 2025. How or will I need to change my taxes?

[VolvoGirl]

You shouldn’t need to change anything.   You can still claim her under 19.   If she has income she may need to file her own return.  

[DoninGA]

Probably not a change for tax year 2025.  But for 2026 if he is not a full time student and has gross income of a certain amount then no one can claim him on a tax return.

You should be able to claim him as your dependent on the 2024 tax return under the Qualifying Child rules if he meets all the requirements.

To be a Qualifying Child -

1. The child must be your son, daughter, stepchild, foster child, brother, sister, half brother, half sister, stepbrother, stepsister, or a descendant of any of them.
2. The child must be (a) under age 19 at the end of the year, (b) under age 24 at the end of the year and a full-time student or (c) any age and permanently and totally disabled.
3. The child must have lived with you for more than half of the year. Temporary absences while away at college are considered living with you.
4. The child must not have provided more than half of his or her own support for the year.
5. If the child meets the rules to be a qualifying child of more than one person, you must be the person entitled to claim the child as a qualifying child.
6. The child must be a U.S. citizen or U.S., Canada or Mexico resident for some portion of the year.
7. The child must be younger than you unless disabled.

[MayaD]

No. You can still claim him/her as dependent. 

 To claim your child as your dependent, your child must meet either the qualifying child test or the qualifying relative test:

• To meet the qualifying child test, your child must be younger than you or your spouse if filing jointly and either younger than 19 years old or be a "student" younger than 24 years old as of the end of the calendar year.
• There's no age limit if your child is "permanently and totally disabled" or meets the qualifying relative test.

Your child might need to file his/her own return even when claimed as dependent on your return. 

Do I need to file my own taxes if I'm a dependent?

[TarponBob]

@MayaD @DoninGA @VolvoGirl   Thank you all for your help. Follow up question, sorry I forgot to ask. I see on the w4 it states multiplying the number of qualifying children under age 17 by $2000, and multiplying the number of other dependents by $500. Will both of my children (oldest will be 18 in 2025, youngest will only be 16) be claimed under the $2000 line for a total of $4000, or will the oldest fall under the $500 credit? Thank you for your help. I really appreciate it. 

[MindyB]

Based on the age of your oldest child, he isn't eligible for the $2,000 tax credit, but may be eligible for the $500 credit. If he lived with you for more than half the year and you financially supported him (you must provide more than 50% of his support) he is a qualifying child for purposes of the $500 Credit for Other Dependents. 

You can read more about it here: What is the $500 Credit for Other Dependents

[TarponBob]

@MindyB @Thank you for your help. Since my oldest will not turn 18 until the first half of 2025, I will have to claim him under the $500 credit for next year taxes? 

[Vanessa A]

If he is 17 now you would claim him for the $500 Other Dependent Credit as he is not eligible for the Child Tax Credit since he is not UNDER 17 (16 or younger)
As for 2025, if he is still in school full time for at least 5 months of 2025, then yes, you would also claim him for the $500 Other Dependent Credit again next year if he continues to live with you after graduation (going away to college counts as living with you) and does not provide more than half of his own support.