How to make one time additional estimated tax payment?

Forum|Forum|6 months ago
November 17, 2025
1 reply
2 views

I made some unexpected capital gain later this year. And my regular tax withheld from paycheck does not seem to be enough. I am concerned I will underpay the tax this year. I wonder how should I make one time payment to the IRS? Is this called estimated tax payment?
If so, which form should I choose to pay for? 1040? or 1040ES? And how should I file this with TurboTax later next year? Do I get a form to import to TurboTax?

TurboTax Premier Online

Best answer by baldietax

Expert Reviewed

Thank you. I see.
So compared to make one big estimated tax payment, would it be better if I try to withheld as much as I can through paycheck and pay a smaller amount one time estimated tax? That way my payment from paycheck breaks down to each quarter are higher, I may end up owing few tax penalty or interest, right?

Yes to the extent you can increase withholding it will reduce the amount of ES owed, and therefore any penalty from the ES being late. ES = Safe Harbor - Withholding (and then divide by 4 for what is due per quarter by default). This is what Form 2210 is calculating on Lines 1-9, suggest reviewing that.

It sounds like you increased withholding for the August gain/loss which was the right thing to do (any maybe helped meet your safe harbor already based on prior year tax?). The only problem for the rest of 2025 is there isn't much time left to increase your withholding, by the time payroll provider processes maybe you can get it higher for December.

All this should go into your 2026 planning also - when you file with TT it will generate ES vouchers by default assuming you need to meet 100/110% of your 2025 tax liability, less withholding (which is assumed for 2026 to be the same as 2025). Sometimes this estimate is too high if your situation is steady you only need to pay 90% of 2026 tax. You can update these assumptions under Other Tax Situations / Form W4 and Estimated Taxes including estimates of 2026 income and withholding to optimize the ES projection. If you anticipate more gain/loss in 2026 or say a Roth conversion you may be better off just planning quarterly ES payments based on prior year tax. You can also adjust the ES payments lower later in the year if you revise your estimates and don't need to pay as much, but you can't increase or make one-off ES later in the year to make up for income earlier in the year without a penalty; but you can use withholding any time...

Bsch4477

Level 15

Yes, it’s an estimated payment and the details are here with a link to the 1040-ES form. When you do your return you report the payment in your TurboTax program.

superlycAuthor

Level 5

So, I should choose 1040 ES? How should I report this with Turbox then? I never did this before so. Is there a tax form to upload to Turbox after I made this estimated tax payment?

Bsch4477

Level 15

Yes. Send the completed 1040-ES Form with your check to the IRS. There’s nothing else to do. The TurboTax program has an area in the program for you to report your payment and the program puts that amount in the proper line in your return. You don’t have to do anything else.