In order for your child to be your dependent, for ages 19-23, he must have been a full time student for parts of 5 calendar months or have made less than $4200.
So, unfortunately, it hinges on whether the fall term started in August or September. If he was enrolled in school, any time in August, even if classes didn't start until September, he meets the 5 month requirement.
Even if he is not your dependent, you may still claim the 529 plan earnings exclusion. It is not necessary that he be your dependent. It is only necessary that he be the beneficiary of the 529 plan. The TurboTax interview can handle this.
But, you can just not report the 1099-Q, at all, if your student-beneficiary has sufficient educational expenses, including room & board (even if he lives at home) to cover the distribution. When the box 1 amount on form 1099-Q is fully covered by expenses, TurboTax will enter nothing about the 1099-Q on the actual tax forms. But, it will prepare a 1099-Q worksheet for your records.
On form 1099-Q, instructions to the recipient reads: "Nontaxable distributions from CESAs and QTPs are not required to be reported on your income tax return. You must determine the taxability of any distribution."
You didn't ask, but be advised that you can not claim a tuition credit, if he is not your dependent. He can not claim the refundable tuition credit, because he does not support himself with earned income. The other credits will do him no good, as he (apparently) has no net taxable income.
@Nicole0808
