Quarterly Estimated Tax Calculator (2026)
See how much to pay the IRS each quarter so you don’t face an underpayment penalty. Uses the 1040-ES safe harbor rules.
| Payment | Amount |
| Q1 · due April 15, 2026covers Jan 1 – Mar 31, 2026 | |
| Q2 · due June 15, 2026covers Apr 1 – May 31, 2026 | |
| Q3 · due September 15, 2026covers Jun 1 – Aug 31, 2026 | |
| Q4 · due January 15, 2027covers Sep 1 – Dec 31, 2026 |
| Estimated total tax for 2026 | |
| Safe-harbor amount to pay | |
| Withheld from W-2 pay | |
| Already paid | |
| Still to pay |
How this is calculated
First we estimate your total 2026 federal tax (income tax plus self-employment tax) from the numbers you enter, using the same method as our self-employment tax calculator.
Then we apply the IRS safe harbor. The amount you need to pay through withholding and estimates is the lower of:
- 90% of this year’s estimated tax, or
- 100% of last year’s total tax (110% if last year’s AGI was over $150,000).
We subtract your W-2 withholding and anything you’ve already paid, then split what’s left evenly over the due dates that haven’t passed.
Figures for tax year 2026. Full method and sources on our methodology page.
Common questions
Who has to pay quarterly estimated taxes?
Generally, anyone who expects to owe $1,000 or more when they file, after withholding and credits. That includes most freelancers, 1099 contractors and gig workers who earn a meaningful side income.
What is the safe harbor rule?
You avoid the underpayment penalty if your withholding and estimated payments cover at least 90% of this year’s tax, or 100% of last year’s tax (110% if last year’s adjusted gross income was over $150,000). This calculator picks whichever is lower.
I missed a quarter. What should I do?
Pay as soon as you can. The penalty works like interest on the amount that was late, so paying sooner keeps it small. This calculator spreads what you still owe across the remaining due dates.
How do I pay?
Online through IRS Direct Pay or your IRS online account (choose “Estimated tax” and Form 1040-ES), by debit or credit card through an IRS-approved processor, or by mailing a check with a 1040-ES voucher.
Can I raise my W-2 withholding instead?
Yes. If you also have a job, increasing withholding on your W-4 counts as paid evenly through the year, which can cover earlier quarters you missed.
Last updated September 28, 2026. This calculator gives an estimate for federal taxes only and isn’t tax advice. State and local taxes aren’t included.