How do I know if a federal tax refund was applied to the following year's taxes. Uncle Dewey

To determine if a Federal Tax Refund was applied to a following year's taxes, you will need to view your Form 1040 Line 77 or Form 1040A Line 49.

You can also view your IRS Tax Account Information by clicking here: https://www.irs.gov/payments/view-your-tax-account.