I filed an extension by myself and now I would like to pay my taxes through TurboTax in September 2025 for my 2024 taxes. How I pay the interest because of my extension?

[emretelli2002]

I prepared my taxes in TurboTax but there is no option to pay additional interest because of extension here. How can I pay it together?

[rjs]

Just file your tax return and pay the tax that you owe. The IRS will send you a bill for the interest and penalty. TurboTax is not able to calculate the exact amount of interest.

[VolvoGirl]

You can’t figure it.   The IRS will mail you a bill for any interest and penalties.   

[Mike9241]

not only is there interest but also a late payment penalty of .5% a month. being more than 5 months late that's an additional 3% of what's owed. as stated the IRS will bill you.