I received disability insurance income in 2017 but there was an overpayment made to me. I returned the overpayment amount in 2018. How does this get reported?

Before you proceed, not all disability insurance is considered taxable income. 

If your disability income is not taxable, don't report it on your income tax return.

Click here to find out if your disability income is taxable.

If you received taxable disability income, that you repaid, check out TurboTaxMichael DC's answer:

https://ttlc.intuit.com/replies/6068496

Edited 2/7/18 1:44 p.m.

Edited 2/7/18 1:44 p.m.