2026 US Self-Employment Tax Calculator

Self-employment tax (SE tax) specifically covers Social Security (12.4%) and Medicare (2.9%) contributions — the same taxes withheld from a traditional employee's paycheck, but paid in full by the self-employed person. Income tax is separate and is calculated on your net profit minus the 50% SE deduction and any other deductions. This calculator only estimates your SE tax — your total federal tax bill will be higher once ordinary income tax is added.

The IRS allows you to reduce your net profit by 7.65% before calculating SE tax. This accounts for the fact that employed workers only pay half of the total 15.3% FICA tax — their employer pays the other half. Since self-employed individuals pay the full 15.3%, multiplying by 92.35% (which equals 1 − 0.0765) provides an equivalent adjustment. It's a built-in fairness mechanism that slightly reduces the tax base.

The Additional Medicare Tax is a 0.9% surtax introduced by the Affordable Care Act, effective since 2013. It applies to net self-employment income above $200,000 for single filers, $250,000 for married filing jointly, and $125,000 for married filing separately. Unlike the base Medicare tax, this additional 0.9% has no employer match — the self-employed person pays the full amount. This calculator includes it automatically based on your filing status selection.

The Social Security Wage Base for 2026 is $176,100. This means the 12.4% Social Security portion of SE tax only applies to your first $176,100 of net self-employment income (after the 92.35% adjustment). Income above this cap is still subject to the 2.9% Medicare tax and the 0.9% Additional Medicare Tax if applicable — but the 12.4% SS portion stops. The IRS typically adjusts this figure annually for inflation.

Yes, but there is a minimum threshold. You must pay SE tax if your net self-employment earnings are $400 or more in a tax year. Below $400, no SE tax is owed. However, even if you don't owe SE tax, you may still need to file a tax return depending on your total income. If you have multiple income sources, self-employment income from all of them is combined when determining whether you exceed the $400 threshold.

The IRS generally waives the underpayment penalty if you meet one of two safe harbors: (1) you pay at least 90% of your current year's tax liability through estimated payments and withholding, or (2) you pay 100% of last year's total tax liability (110% if your prior-year AGI exceeded $150,000). The second safe harbor is often easier to calculate and plan for — simply divide last year's total tax by 4 and pay that amount each quarter. This calculator's quarterly estimate helps you stay within the 90% threshold.

You can deduct 50% of your total SE tax as an above-the-line deduction on Form 1040, Schedule 1. This is the employer-equivalent portion of the tax. It reduces your Adjusted Gross Income (AGI) directly — not just your taxable income — which can positively affect your eligibility for other deductions and credits. The 50% AGI deduction is shown in the calculator above as a separate line. You don't need to itemize deductions to claim it.

Self-employment tax is calculated on Schedule SE (Form 1040) and reported as part of your annual Form 1040. Your net profit from business activity comes from Schedule C. Quarterly estimated payments are made using Form 1040-ES. If you have a net loss from self-employment, you generally don't owe SE tax for that year — but losses can be carried forward or back in certain situations. Always retain records of all quarterly payments as confirmation of timely filing.