Quarterly Estimated Tax Calculator
Work out quarterly estimated tax payments that satisfy IRS safe-harbor rules so you avoid an underpayment penalty.
Your numbers
- Safe-harbor target
- $19,000
- 90% of current year
- $21,600
- 100% of prior year
- $19,000
How the quarterly estimated tax calculator works
Safe harbor requires paying the smaller of 90% of this year’s tax or 100% of last year’s tax (110% if prior AGI exceeded $150,000), minus withholding, in four installments.
Example
Using the default inputs (Expected total tax this year: $24,000; Total tax last year: $19,000; Last year’s AGI: $120,000; Expected withholding & credits: $4,000), the calculator returns each quarterly payment of $3,750. Change any field above to see your own result and charts update instantly.
Good for these goals
Frequently asked questions
When are payments due?
April 15, June 15, September 15 and January 15 of the following year.
Who must pay?
Anyone expecting to owe $1,000 or more after withholding, typically freelancers and investors.
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Estimates are for educational purposes only and are not financial, tax or legal advice. Results depend on your inputs and simplified assumptions; tax figures reflect 2026 federal rules and may differ from your situation. See our disclaimer. © 2026 FinanzCalc.