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Quarterly payments

Estimate your quarterly tax payments for 2026

Start with the annual income, annual federal tax, and withholding numbers you want to test, then turn the remaining gap into reviewed 2026 quarterly payments. Prior-year tax and AGI stay optional and only unlock the safe-harbor comparison.

U.S. tax onlyEducational estimates, not tax advice.
Reviewed federal tax year: 2026Last updated: March 31, 2026

Calculator inputs

Enter the details for an educational estimate

Include both income tax and self-employment tax in this full-year federal estimate.

Include W-2 withholding or other federal withholding already expected for this year.

Use your best current full-year income estimate so this route can keep the annual tax and withholding inside a visible range check before showing the payment schedule.

Add both prior-year fields to show a simplified safe harbor reference beside the equal-installment estimate.

Used only to decide whether the simplified prior-year safe harbor reference uses 100% or 110%.

Estimate result

Estimated quarterly payment

Enter the reviewed year, annual income, annual federal tax, and withholding to see the installment estimate. Add prior-year tax plus AGI only if you want the safe-harbor reference.

U.S. tax only

Educational estimates, not tax advice.

Trust and disclosure

Check the method before you rely on this estimate

Educational estimate only. Uses 2026 federal due dates and simplified equal-installment math. Not tax, legal, or financial advice. It does not replace Form 1040-ES or the annualized income installment method.

Reviewed federal tax year: 2026

Last updated: March 31, 2026

Estimate method

How this estimate works

  • Start with the annual income, annual federal tax, and expected withholding you want to test. Annual income stays visible so the route can reject annual tax or withholding values that exceed the income entered.
  • Subtract expected annual withholding to estimate the remaining annual gap that still has to be covered outside payroll withholding.
  • Allocate that remaining annual gap across four quarterly installments using the reviewed due-date set for the selected year and reconcile any one-cent rounding remainder inside the schedule.
  • If prior-year tax and AGI are provided, show a simplified safe-harbor reference as a comparison point instead of replacing the main equal-installment result.
  • Keep annualized-income methods, penalty calculations, and quarter-by-quarter catch-up logic outside this route so the estimate stays legible and within scope.

Reviewed scenarios

Worked examples

Approved example QE26-04Reviewed tax year 2026

Equal-installment without prior-year inputs

With $20,000.00 of estimated annual federal tax and $5,000.00 of expected withholding, this reviewed example lands near $3,750.00 per quarter without a safe-harbor overlay, with the installment table reconciling any one-cent rounding remainder. It is the clearest baseline for understanding how withholding alone changes the annual gap.

Reviewed assumptions

  • This worked example uses the equal-installment method across four quarterly payments.
  • The prior-year safe-harbor reference stays optional and does not replace the current-year installment result.

Traceability checks

  • Expected withholding is subtracted before the annual gap is allocated across the quarterly installment schedule.
  • The route keeps the reviewed quarterly due-date schedule visible beside the installment math.
  • The safe-harbor reference is shown only when both prior-year inputs are provided.
Approved example QE26-06Reviewed tax year 2026

Safe-harbor comparison example

In this reviewed example, the current-year equal installment is about $6,000.00, while the simplified safe-harbor reference comes out near $4,125.00. The route keeps the lower educational quarterly estimate at about $4,125.00, which helps explain why both numbers stay visible together.

Reviewed assumptions

  • This worked example uses the equal-installment method across four quarterly payments.
  • The prior-year safe-harbor reference stays optional and does not replace the current-year installment result.

Traceability checks

  • Expected withholding is subtracted before the annual gap is allocated across the quarterly installment schedule.
  • The route keeps the reviewed quarterly due-date schedule visible beside the installment math.
  • The safe-harbor reference is shown only when both prior-year inputs are provided.
Approved example QE26-08Reviewed tax year 2026

Large-balance quarterly example

In this reviewed example, the remaining annual balance is about $100,000.00. That leaves the displayed quarterly estimate near $12,500.00, while the optional safe-harbor reference stays around $12,500.00. It shows how a larger annual gap can keep the current-year path in front even when the safe-harbor check is available.

Reviewed assumptions

  • This worked example uses the equal-installment method across four quarterly payments.
  • The prior-year safe-harbor reference stays optional and does not replace the current-year installment result.

Traceability checks

  • Expected withholding is subtracted before the annual gap is allocated across the quarterly installment schedule.
  • The route keeps the reviewed quarterly due-date schedule visible beside the installment math.
  • The safe-harbor reference is shown only when both prior-year inputs are provided.

Questions about this quarterly payment estimate

Disclaimer

Educational estimate only. Uses 2026 federal due dates and simplified equal-installment math. Not tax, legal, or financial advice. It does not replace Form 1040-ES or the annualized income installment method.

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