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Form 2210 Underpayment Penalty Estimator for 2026 Estimated Tax

What does this come to under the current IRS rules?

Penalty on each 2026 installment shortfall by rate period, using the 2026 quarterly underpayment rates.

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Your figures
Example figuresIllustrative only. Type over them with your own.
Estimated penalty
$367
Regular method, unpaid through April 15, 2027
Installment 1 penalty
$136
Installment 2 penalty
$116
Drawn to one scale
Estimated penalty$367
Installment 1 penalty$136
Installment 2 penalty$116
Installment 3 penalty$81
Installment 4 penalty$35
All results
MeasureResult
Estimated penalty
Underpayments assumed unpaid until April 15, 2027
$367
Installment 1 penalty$136
Installment 2 penalty$116
Installment 3 penalty$81
Installment 4 penalty$35
How this was worked out
Work shownrecomputed as you type
Penalty per period = underpayment x days unpaid in the period / 365 x period rate
Periods: April 16 to June 30, 2026 at 6%; July 1 to September 30 at 7%; October 1 to December 31 at 7%; January 1 to April 15, 2027 at your entered rate
Days used: 76, 92, 92 and 105 for the April installment; the June installment starts June 16; September starts September 16; January starts January 16, 2027

Illustrative arithmetic on the figures you enter. Check the result against your firm's methodology before relying on it.

The formulas

  • Penalty per period = underpayment x days unpaid in the period / 365 x period rate
  • Periods: April 16 to June 30, 2026 at 6%; July 1 to September 30 at 7%; October 1 to December 31 at 7%; January 1 to April 15, 2027 at your entered rate
  • Days used: 76, 92, 92 and 105 for the April installment; the June installment starts June 16; September starts September 16; January starts January 16, 2027

How it works

The Form 2210 regular method figures the penalty separately for each installment: the underpayment times the days it stayed unpaid divided by 365, times the rate for each rate period, ending on April 15 of the next year or the payment date if earlier. The structure follows the 2025 Form 2210 instructions, the latest posted.

The IRS quarterly rate page sets the individual underpayment rate at 7% for January to March 2026, 6% for April to June, 7% for July to September and 7% for October to December. The rate for January to March 2027 was not published when this tool was built, so enter it. Use the estimated tax safe harbor calculator first to find each required installment.

Illustrative figures only. Check the result against your firm's methodology before relying on it.

Common questions

Is the Form 2210 penalty compounded?

No. The worksheet applies simple interest to each installment's underpayment for the days it was unpaid.

What if I paid the shortfall before April 15, 2027?

The penalty stops on the payment date. Count fewer days in the last periods; this tool assumes no payment until April 15, 2027.

How do I avoid the penalty next year?

Pay each installment on time in the amount the safe harbor requires. The estimated tax safe harbor calculator shows the target.

Sources

Runs in your browser. The figures you type are not sent to CORAA or stored. Check the result against your firm's methodology before relying on it.

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