How much can a child make before you can no longer claim them as a dependent?

It depends on their age and if they are a full-time student.

To qualify as a dependent child, the child must live with you more than half of the year and be under age 19 at the end of 2012, or under age 24 if a full-time student. That's defined as attending school full time for at least part of five calendar months of the year -- whether at home or away at school.

If your child provides more than half of his or her own support, you can't claim the child as a dependent.

To determine if a child qualifies as your dependent, complete the Personal Info section in TurboTax.

Note: There are special rules for children of divorced or separated parents and for persons receiving support from two or more individuals. If you are in this situation, read IRS Publication 504: Divorced or Separated Individuals.

I would suggest going through the interview in the Personal Info section, as Turbo Tax does an excellent job with determining who qualifies as a dependent.

Here are some of the basic rules if the child is over 24 or not a full-time student:

  • Have been a citizen or resident of the United States, or a resident of Canada or Mexico.
  • Did not file a joint income tax return with anyone else.
  • Received more than half his or her support from you. 
  • Had less than $3,800 of income for the entire year. (Generally that amount does not include Social Security benefits.)

And, this link may help as well:

Who is a Dependent?

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