You will need to amend your returns for the past year to reflect that you actually paid those tuition expenses out of your own pocket.
You will need to find or re-create your Form 1098-T or your tuition bills from that year to provide the information needed to claim the tax benefit. Your college financial aid office or bursar should be able to provide some help with this.
When you receive a tuition reimbursement, you are not allowed to claim any education tax benefits in the form of credits or deductions (up to the amount of the reimbursement) because you've already received the benefit as tax-free from your employer (up to $5,250).
I would also check your old W-2s to ensure that none of the reimbursements were included in your wages as this would also affect your tax return amendments. Employers are generally required to include any amount of reimbursement over $5,250 in one fiscal year in taxable wages.
However, you had to repay the reimbursement, so it is as if you did not receive it. Therefore you are able to claim the education expense deduction and any related credits in your amendments in the year in which the expenses were paid.
Of course, if you have not yet filed your 2017 tax return when you do you can claim any 2017 education expenses as well as any education credits you may qualify for.
You can find instructions on how to amend your return for previous years in the FAQ below.
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