How do I apply my refund to back taxes owed?

You do not have to enter anything about that since it will happen automatically.   The IRS knows if you owe federal tax from past years.   If you are getting a refund this year, the IRS will seize the refund and use it to pay toward the back taxes owed.   They will send you a letter a few weeks later.

To apply your current year refund to back taxes (prior year) owed using TurboTax, follow these steps:

1. Open TurboTax: Sign in to your TurboTax account and open your current tax return.
2. Navigate to Federal Taxes: Go to the "Federal Taxes" section.
3. Other Tax Situations: Click on "Other Tax Situations."
4. Additional Tax Payments: Under "Additional Tax Payments," find the option "Apply Refund to Next Year" and click the "Start" or "Update" button.
5. Enter Amount: Enter the amount of your refund you want to apply to your back taxes. This amount will be shown on Form 1040, Line

Reach back out if you need something else. 

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