Quarterly Estimated Tax Calculator (US)

About the Quarterly Estimated Tax Calculator (US)

Work out your estimated tax payments for 2026 the way Form 1040-ES does: the Estimated Tax Worksheet with the self-employment tax, the qualified business income deduction, the Additional Medicare Tax and the Net Investment Income Tax; the safe harbors — 90% of this year’s tax or 100% of last year’s (110% when last year’s AGI was over $150,000, $75,000 married filing separately), 66⅔% for farmers and fishers; the $1,000 test; and the four due dates: April 15, June 15 and September 15, 2026, and January 15, 2027.

Enter last year’s tax and AGI, what you expect to earn this year, your withholding and the payments you have made. You get each quarterly payment, the required annual payment and the safe harbor that sets it, what is still to pay, and an estimate of the underpayment penalty by the regular method of Form 2210, at the IRS rate for each quarter, if you paid late or pay the rest on a day you choose. Nothing you type leaves your browser.

Without a pass the page gives a free preview of your own result: the quarterly payment in full, with the first rows of the due dates and the first step of the working; a Pro pass opens every amount, the copy, the CSV and printing.

Who must pay estimated tax

You must pay estimated tax for 2026 if you expect to owe at least $1,000 after subtracting your withholding and refundable credits, and you expect your withholding and refundable credits to be less than the smaller of 90% of the tax on your 2026 return or 100% of the tax on your 2025 return (a return for all 12 months). That 100% becomes 110% if your 2025 AGI was more than $150,000 ($75,000 if you file separately in 2026). If at least two-thirds of your gross income is from farming or fishing, 66⅔% replaces the 90% and the 110% rule does not apply.

You do not have to pay estimated tax for 2026 if you were a US citizen or resident for all of 2025 and had no tax liability for the full year — your total tax was zero, or you did not have to file. Wages let you avoid estimated payments by raising your withholding with a new Form W-4 ([Form 1040-ES]([object Object]); [Am I required to make estimated tax payments?]([object Object])).

The due dates and how to pay

• 1st payment: April 15, 2026
• 2nd payment: June 15, 2026
• 3rd payment: September 15, 2026
• 4th payment: January 15, 2027 — not needed if you file your 2026 return by February 1, 2027 and pay the entire balance with it.

A due date on a Saturday, Sunday or legal holiday moves to the next business day. Farmers and fishers can pay all their estimated tax by January 15, 2027, or file and pay in full by March 1, 2027. You can pay through your IRS Online Account, IRS Direct Pay, EFTPS, by debit or credit card (with a provider’s fee), or by check or money order with the payment voucher ([Estimated taxes]([object Object])).

The penalty for paying late (Form 2210)

Each installment is a quarter of the required annual payment. If less than that is paid by a due date, the penalty is interest on the amount short, for each day from the due date until it is paid (or April 15, 2027, if earlier), at the IRS underpayment rate of each quarter: 6% a year from April 16 to June 30, 2026, then 7% for July to September and for October to December 2026. For January 1 to April 15, 2027 you enter the rate the IRS sets for that quarter; the calculator opens with 7%, the rate for October to December 2026 ([quarterly interest rates]([object Object])).

Withholding counts as paid evenly on the four due dates, and each payment goes first to the earliest installment still short. If your income came unevenly, the annualized income installment method (Schedule AI) can lower the penalty. The IRS waives it when the underpayment came from a casualty, disaster or other unusual circumstance, or when you retired after reaching age 62 or became disabled in the year or the one before, with reasonable cause ([Instructions for Form 2210]([object Object])).

Official sources

• [IRS Form 1040-ES]([object Object]) — who must pay, the special rules, the due dates and the Estimated Tax Worksheet
• [IRS Instructions for Form 2210]([object Object]) — the required installments, the penalty worksheet and the waivers
• [IRS: Quarterly interest rates]([object Object]) — the underpayment rate of each quarter
• [IRS: Estimated taxes]([object Object]) and the [Interactive Tax Assistant]([object Object])
• [IRS Rev. Proc. 2025-32]([object Object]) — the 2026 tax rate tables, standard deduction and qualified business income thresholds

Limitations

• An estimate for tax year 2026 from the figures you enter: the alternative minimum tax, household employment taxes, the extra tax on early retirement withdrawals and state estimated tax are not included.
• The qualified business income deduction is estimated at 20% only below the income threshold ($201,750, $403,500 married filing jointly); above it, enter your own figure.
• If you marry or stop filing jointly, figure last year’s tax as the Form 1040-ES instructions say (both spouses’ 2025 tax added together, or the joint tax shared out) before you enter it.
• The penalty uses the regular method with withholding spread evenly; Form 2210 also lets you use the actual withholding dates or the annualized income installment method, which can give less. A guide, not tax advice.

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