Quarterly Estimated Tax Calculator

If you're self-employed, a freelancer, or otherwise earn income without tax withholding, the IRS requires you to pay estimated tax four times a year rather than waiting until you file your annual return. This calculator combines your self-employment tax and federal income tax liability into a single quarterly payment schedule using Form 1040-ES rules for the 2026 tax year.

Your total estimated tax liability starts with self-employment tax (12.4% Social Security up to the wage base plus 2.9% Medicare, with an additional 0.9% Medicare surtax above the applicable threshold), calculated exactly the same way as our Self-Employment Tax Calculator. Half of that self-employment tax is then deducted from your income before federal income tax brackets are applied, matching the above-the-line deduction the IRS allows on Schedule 1.

To avoid an underpayment penalty, the IRS uses a "safe harbor" rule: you generally need to pay at least 90% of your current-year tax liability, or 100% of your prior-year tax liability, through withholding and estimated payments. If your prior-year adjusted gross income exceeded $150,000 ($75,000 if married filing separately), the prior-year safe harbor rises to 110% instead of 100%. This calculator compares both thresholds and uses whichever produces the smaller required payment.

If your projected total tax liability for the year is less than $1,000, the IRS does not require any estimated payments at all — this is the "de minimis" exception. Otherwise, your required annual payment is divided evenly across the four 2026 due dates: April 15, June 15, September 15, and January 15, 2027.

This tool is designed for self-employed individuals, freelancers, independent contractors, gig workers, and anyone with significant income not subject to withholding. It is not a substitute for professional tax advice, and actual liability may differ based on deductions, credits, and other income sources not modeled here.