Are Children Tax-Deductible the Year They Turn 18?

Having children brings joy, complications, worries and an extra tax deduction into your life. Though the exemption for children doesn’t approach the cost of actually raising them, it does help lower your taxes. As long as you’re supporting your children, you’ll want to claim them on your taxes, but all good things come to an end and eventually, your tax dependent will be too old to claim. The rules for claiming your child can get complicated, but even when they turn 18 you have time left to claim them on your taxes if they meet certain requirements.

Claiming a child on taxes that is not yours is not out of the realm of possibilities, as long as the child meets IRS requirements. In order for you to deduct your child from your taxes, the child must be your son, daughter, stepson, stepdaughter, adopted child, foster child, brother, sister, stepbrother, stepsister, foster child, niece, nephew, half sister, half brother or grandchild. He must live with you for more than half the year, and the child cannot provide more than half of his own support. Though in many jurisdictions an 18-year-old is considered an adult, IRS rules stipulate that you can claim a deduction for your child as long as she is younger than 19 at the end of the year. The year she turns 18, no matter if her birthday falls on Jan. 1 or Dec. 31, you can still claim her, as long as she meets all the other requirements for a deduction. The following year you may have to give up that deduction, unless she’s in school full-time. If your child is permanently disabled, the IRS waives the age requirement altogether. If your child is a full-time student who relies on you for support, you can continue to deduct him from your taxes until he turns 24 or graduates, whichever comes first. Your child must be enrolled full-time in school, and he must be younger than you or your spouse.

If you’re divorced, separated or never-married, and the other parent has custody, you may not meet this residency requirement, even though you provide more than half of your child’s support. In this case, you can still claim your child as a deduction if your spouse agrees. Some couples alternate the years they claim a child. The custodial parent must complete Form 8332, Release/Revocation of Release of Claim to Exemption for Child by Custodial Parent, and you must file this form with your tax return. If your 18-year old is married and files a tax return with his spouse, you can’t claim him as a dependent, unless the couple have no taxable income and merely filed the claim to obtain a refund. If your 18-year old is living on his own and not a student, you can no longer claim him on your taxes. If your child is legally emancipated, you can’t claim him as a dependent. If your child supplies more than half of his own support, you aren’t entitled to list him as a dependent.

If your child has not yet reached the child tax credit age limit, it's important to pay close attention to the changes to the credit. The limit to claim it is age 17, so you may still have time if your child hasn't yet reached his 18th birthday. Thanks to changes in tax laws, moving forward you can claim $2,000 per qualifying child, with the credit being refundable up to $1,400, subject to phaseouts. Phaseouts begin if your household has an adjusted gross income of $400,000 per married couple filing jointly or $200,000 per individual taxpayer.

If your tax dependent hadn't yet turned 18 in the 2017 tax year, you should be able to claim a Child Tax Credit of up to $1,000 per qualifying child. The refundable amount is limited to 15 percent of earnings up to $3,000.