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Late Filing and Late Payment Penalty Calculator (IRC 6651)

What do these figures come to once the work is shown?

Failure to file and failure to pay additions to tax, with the monthly overlap reduction, the 25 percent caps and the minimum penalty.

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Your figures
Example figuresIllustrative only. Type over them with your own.
Total additions to tax
$1,500
Penalties only, before interest
Failure to file addition
$1,350
Failure to pay addition
$150
Drawn to one scale
Total additions to tax$1,500
Failure to file addition$1,350
Failure to pay addition$150
All results
MeasureResult
Total additions to tax
Interest is not included
$1,500
Failure to file addition$1,350
Failure to pay addition$150
Total as a share of the tax15.00%
How this was worked out
Work shownrecomputed as you type
Failure to file = 5% per month or part, up to 25% (5 months)
Failure to pay = 0.5% per month or part, up to 25% (0.25% with a timely filed return and an installment agreement)
Months where both apply: the filing addition is reduced by the 0.5% for that month
More than 60 days late: filing addition at least the lesser of $535 and 100% of the tax (returns required in 2027)

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

The formulas

  • Failure to file = 5% per month or part, up to 25% (5 months)
  • Failure to pay = 0.5% per month or part, up to 25% (0.25% with a timely filed return and an installment agreement)
  • Months where both apply: the filing addition is reduced by the 0.5% for that month
  • More than 60 days late: filing addition at least the lesser of $535 and 100% of the tax (returns required in 2027)

How it works

Section 6651 adds 5 percent of the unpaid tax for each month or part of a month a return is late, up to 25 percent, and 0.5 percent a month for late payment, up to 25 percent. In a month when both apply, the filing addition is cut by the payment addition, so the two together run at 5 percent a month for the first five months.

If a return is filed more than 60 days late, the filing addition is at least the lesser of a minimum dollar amount or the tax. Rev. Proc. 2025-32 sets that amount at $535 for returns required to be filed in 2027, which are 2026 returns. Fraud penalties, extensions and reasonable cause relief are not modeled.

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

Common questions

Is a part of a month a full month?

Yes. The statute counts each month or fraction of a month.

Does the statute page show the same minimum?

The statute text shows an older $435, which is indexed. The 2027 return figure of $535 comes from Rev. Proc. 2025-32.

How is the 60 day test measured?

Rev. Proc. 2025-32 measures it from the due date of the return determined with regard to any extension of time to file. Enter the days late from that date.

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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