Tax Extension Calculator
Calculate balance due and penalties when filing a tax extension (Form 4868).
Balance Due
$0.00
Penalty if Unpaid by Oct 15
$0.00
Total Owed by Oct 15
$0.00
Extension Details
| Estimated Tax | $0.00 |
| Already Paid / Withheld | $0.00 |
| Balance Due Now | $0.00 |
| Late Payment Penalty (6 mo) | $0.00 |
| Interest (6 mo) | $0.00 |
File Form 4868 by April 15 for automatic extension to October 15. Extension is to file, not to pay — interest and penalties accrue on unpaid balances.
Use the Tax Extension Calculator above to calculate your results. Enter your values and see instant results — all calculations run in your browser.
Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.
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