Estimated Quarterly Tax Calculator
The IRS requires taxpayers with income not subject to withholding to make quarterly estimated tax payments throughout the year. To avoid the underpayment penalty, the IRS safe-harbor rules allow you to pay the lesser of 90% of your current-year tax liability or 100% of your prior-year tax (raised to 110% if your prior-year adjusted gross income exceeded $150,000). This calculator uses those safe-harbor rules to compute your quarterly payment amounts. Enter your estimated current-year tax and your prior-year tax to see which safe-harbor amount is lower and what you should pay each quarter.
Estimated tax safe-harbor formula
Option A = current-year tax * 0.90
Option B = prior-year tax * 1.00 (or * 1.10 if prior AGI > $150,000)
Safe-harbor annual amount = min(Option A, Option B)
Quarterly payment = safe-harbor amount / 4
You avoid the underpayment penalty by paying the lesser of Option A or Option B across the four quarterly deadlines. If your income is uneven, consider the annualized income installment method on Form 2210.
Estimated tax payment rules
- 2025 payment due dates: April 15, June 16, September 15, and January 15, 2026.
- The penalty for underpayment is calculated using the federal short-term interest rate plus 3 percentage points, compounded daily.
- You can pay online using IRS Direct Pay (free), EFTPS (free), or by check with Form 1040-ES vouchers.
- Withholding from wages or other sources counts toward your estimated tax obligation and may eliminate the need for separate estimated payments.
- If you expect to owe less than $1,000 after withholding and credits, you generally do not need to make estimated payments.
Estimated quarterly tax: frequently asked questions
What is the safe harbor for estimated taxes?
You avoid underpayment penalties if you pay the lesser of 90% of the current year's tax liability or 100% of last year's tax (110% if your prior-year AGI exceeded $150,000). This ensures you are protected even if your income rises significantly.
When are estimated tax payments due in 2025?
The four estimated tax payment deadlines for the 2025 tax year are April 15, June 16, September 15, and January 15, 2026. These cover the Q1, Q2, Q3, and Q4 periods respectively.
Who needs to make estimated tax payments?
You generally must make estimated payments if you expect to owe at least $1,000 in federal tax after withholding and credits. Self-employed individuals, investors, and anyone with significant non-withholding income typically need to pay quarterly.
What form is used to pay estimated taxes?
IRS Form 1040-ES is used to calculate and submit estimated tax payments. You can pay online at IRS Direct Pay, by mail with the voucher, or by electronic funds withdrawal. The IRS also accepts payment via EFTPS.
Can I adjust my estimated payments during the year?
Yes. Estimated payments are separate each quarter, so you can increase or decrease later quarters if your income changes. The annualized income installment method (Form 2210 Schedule AI) allows uneven income earners to align payments with when income is received.
Official sources
- IRS: About Form 1040-ES, Estimated Tax for Individuals.
- IRS: Publication 505 (Tax Withholding and Estimated Tax).
Reviewed by the CalculatorHub team, edited by James Graham, 15 June 2026. See our methodology.