Free tool

Quarterly estimated tax calculator

If you are self-employed in the US, the IRS expects estimated payments four times a year. Enter a few numbers and see what to pay by June 15 or September 15 to stay penalty-safe, with the full self-employment and income-tax math shown so you can check it.

Pick the deadline you are paying toward. Q2 covers payments through June 15; Q3 through September 15.
Your expected profit after business expenses for the whole year (Schedule C net).
$
Total federal tax from last year's return (line 22 of your 2025 Form 1040). Used for the prior-year safe harbor.
$
Last year's adjusted gross income. Above $150,000 raises the prior-year test from 100% to 110%.
$
Federal estimated tax you have already paid this year, across earlier quarters.
$

Enter your expected net self-employment income above to see what to pay this quarter.

This sizes a federal estimate only, for a single self-employment income source. It ignores other household income, the QBI deduction, tax credits, the Additional Medicare Tax on high earners, and all state and local tax. It is a planning estimate and never files anything for you.

General guidance, not tax advice. Confirm with your accountant. Canada works differently and is not modeled here.

Common questions

Quarterly taxes, plainly.

How much should I pay in quarterly estimated taxes?

The IRS safe-harbor rules let you avoid an underpayment penalty if your total estimated payments cover the smaller of 90% of this year's tax or 100% of last year's tax (110% if your prior-year AGI was over $150,000). This calculator works out both numbers, picks the cheaper one, and shows what is due for the quarter you select.

When are 2026 quarterly estimated taxes due?

Federal estimated taxes for 2026 are generally due April 15, June 15, and September 15 of 2026, then January 15, 2027. This tool covers the Q2 (June 15) and Q3 (September 15) deadlines, the two most people search for mid-year.

Does this include self-employment tax?

Yes. Self-employed people owe both income tax and self-employment tax (Social Security plus Medicare). The calculator computes SE tax on 92.35% of your net earnings, caps the Social Security portion at the 2026 wage base, and adds the income-tax projection on top. The breakdown panel shows every step.

What does this calculator leave out?

It estimates federal tax only for a single Schedule C income source. It ignores other household income, the QBI deduction, tax credits, the Additional Medicare Tax on high earners, and all state and local taxes. It never files anything. Treat it as a planning estimate and confirm the final numbers with your accountant.

General guidance, not tax advice. Confirm with your accountant. Canada works differently: there is no federal Schedule C, and self-employed Canadians follow CRA instalment rules instead.

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