You may be able to claim your son as a Qualifying Child dependent if: (health insurance notwithstanding for both depenents below):
- The child must be related to you. The child can be your son, daughter, stepchild, eligible foster child, brother, sister, half-brother, half-sister, stepbrother, stepsister, adopted child or an offspring of any of them.
- Your child must be under age 19 or, if a full-time student, under age 24. There is no age limit if your child is permanently and totally disabled.
- Your child must live with you for more than half the year, but several exceptions apply (ie. away at school).
- The child cannot provide more than half of his/her support.
- You must be the only person claiming the child
- The child must be a US citizen, resident alien, national, or resident of Mexico or Canada.
- The child cannot file a joint return with his or her spouse.
You may be able to claim your son as a Qualifying Relative dependent if:
- You provided more than half of his support in 2016
- He earned less than $4,050 in gross taxable income. (Social Security income generally doesn’t count here.)
- He lives with you 365 days in the year or is related to you.
- He isn’t a dependent on someone else’s tax return.
- He isn’t filing a tax return with a spouse (married filing jointly).
- He is a U.S. citizen, resident alien, national, or a Canadian or Mexican resident
You can’t claim a dependent if you are a dependent on someone else’s taxes
The rules above will qualify you to cliam your son even though he files his own return although two individuals cannot cliam the same exemption. For instance, if you are eligible to claim him per the above, he should not have claimed himself. If he did so, he should amend his return.