I owe for my 2025 tax return and also need to pay Q1 2026 estimated tax. Do I make two separate IRS payments?

Yes, in most cases you should treat them as two separate payments with two separate payment reasons. Your 2025 return balance is a balance due for tax year 2025. Your Q1 2026 estimated tax is a Form 1040-ES estimated payment for tax year 2026.

Why this matters: the IRS posts payments based on the payment type and tax year you select. If you send one payment under the wrong category, it may not get applied where you intended. That can create notices, interest, or an underpayment issue even if you paid enough money overall.

Best practice:

• Pay the 2025 balance due using IRS Direct Pay, EFTPS, or your tax software under the option for balance due or income tax return for 2025.
• Make a separate estimated tax payment for 2026 Q1 under Form 1040-ES.
• Save both confirmation numbers.

Can you pay both on the same day? Yes. They just need to be coded correctly.

Do you need the Q1 2026 payment at all? Usually yes if you expect untaxed income in 2026, such as self-employment income, investment gains, or a Roth conversion, and you want to avoid an underpayment penalty. A common safe-harbor rule is to pay at least 100% of your prior-year total tax through withholding and estimates, or 110% if your prior-year AGI was above the IRS threshold.

If you are unsure how much to send, the IRS Tax Withholding Estimator can help for wage income, and Form 1040-ES worksheets can help for estimate calculations.