This a personal (nonbusiness) bad debt. It can be deducted on your tax return.
It is entered in the Investments section. It is listed under "Other" assets sold as it will be shown as a short term capital loss.
The sale price is shown at $0, the sales date is date it became worthless.
The purchase price or cost is the amount owed to you and the date of the debt.
To
enter your Nonbusiness Bad Debt
Click
on Federal Taxes
Click
on Wages and Income
Click
on I'll choose what I work on
Scroll
down to Investments
On
Stocks, Bonds, Other, click the start or update button
Enter it here.
You will need some evidence of this debt for your tax records so I recommend you look at the below link.
See this link for detail
https://turbotax.intuit.com/tax-tools/tax-tips/Tax-Deductions-and-Credits/How-to-Report-Non-Business...
