Estimated Tax Penalty Calculator
Estimate IRS underpayment penalties for estimated taxes using safe harbor rules, quarterly payment analysis, and current IRS interest rates.
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Quarterly payments & safe harbor analysis
Total tax on your return (line 24 of Form 1040)
Total tax from last year's return
For 110% safe harbor: AGI > $150K ($75K MFS)
W-2 and 1099 withholding for the year
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Enter your tax liability, withholding, and estimated payments to check safe harbor status and estimate any underpayment penalty.
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