Quarterly Estimated Tax Calculator
Calculate your quarterly estimated tax payments to avoid underpayment penalties. See due dates and safe harbor thresholds.
📅 Tax Year:
Calculate Quarterly Payments
$
Income tax + SE tax combined
$
$
From last year's return
How It Works
If you expect to owe $1,000 or more in taxes after withholding, you generally must make quarterly estimated tax payments or face penalties.
Due Dates
| Period | Due Date |
|---|---|
| Jan 1 – Mar 31 | April 15 |
| Apr 1 – May 31 | June 15 |
| Jun 1 – Aug 31 | September 15 |
| Sep 1 – Dec 31 | January 15 (next year) |
Safe Harbor Rules
To avoid penalties, pay the lesser of:
- 90% of current year's tax liability, OR
- 100% of prior year's tax (110% if AGI > $150,000)
Also, no penalty if you owe less than $1,000 after withholding and credits.
Examples
Example: $25,000 Estimated Tax, $5,000 Withholding
Remaining: $20,000
Quarterly payment: $20,000 ÷ 4 = $5,000
Frequently Asked Questions
What if I miss a quarterly payment?
You may owe an underpayment penalty calculated for the period you
were underpaid. Pay as soon as possible to minimize the penalty.
Can I make unequal quarterly payments?
Yes, you can use the annualized income installment method if your
income is irregular, but equal payments are simpler.
How do I make payments?
Pay online at IRS.gov/payments, by mail with Form 1040-ES vouchers,
or by phone. Electronic payment is fastest and creates a clear record.
What is the 110% rule?
If your AGI exceeded $150,000 last year ($75,000 if MFS), the safe
harbor is 110% of prior year tax instead of 100%.
Do estimated payments include SE tax?
Yes, your estimated payments should cover both income tax and
self-employment tax. Calculate both when determining your total estimated tax.
What if my income fluctuates?
You can adjust payments as the year progresses. If income is lower
than expected, reduce later payments. If higher, increase them.
Use Cases
- Self-employed freelancers and contractors — determine each quarterly voucher amount so you stay ahead of IRS deadlines.
- Small-business owners without payroll withholding — avoid year-end surprises by spreading tax payments across four quarters.
- Investors with significant capital gains — estimate additional tax owed on realized gains outside of W-2 withholding.
- Retirees with pension or rental income — calculate payments when income is not subject to employer withholding.
- Side-income earners — figure out whether you need to make estimated payments based on the $1,000 threshold.
Assumptions & Limitations
- The calculator divides the remaining tax equally across four quarters; it does not use the annualized income installment method.
- Safe harbor thresholds follow the 100%/110% prior-year rule based on whether AGI exceeds $150,000.
- Due dates assume standard IRS deadlines. If a due date falls on a weekend or holiday, the actual deadline shifts to the next business day.
- State estimated tax obligations are not included in this calculation.
- Credits (such as the earned income credit or child tax credit) are not factored in; enter your net expected tax after credits.
- Results are estimates for planning purposes only. Consult a qualified tax professional or the IRS for your exact liability.
Sources & References
- IRS Form 1040-ES Instructions — Estimated Tax for Individuals
- IRS Publication 505 — Tax Withholding and Estimated Tax
- IRS Publication 334 — Tax Guide for Small Business
- IRS Revenue Procedure 2025-11 — 2026 inflation-adjusted amounts
- IRS Publication 17 — Your Federal Income Tax
- 26 U.S. Code § 6654 — Failure to pay estimated income tax
This calculator is provided for informational purposes only and does not constitute tax, legal, or financial advice. Always verify figures with official IRS publications or a licensed tax professional.