How do I apply my federal refund to my 2025 taxes?

[DoninGA]

To add, change or delete a current year federal tax refund to next year's taxes before you file your tax return -

Click on Federal Taxes (Personal using Home and Business)
Click on Other Tax Situations
Under Additional Tax Payments
On Apply Refund to Next Year, click on the start or update button

The amount applied to next years taxes will be shown on Form 1040 Line 36