How the 2026 Self-Employment Tax Estimate Works
Self-employment tax generally applies Social Security and Medicare tax to 92.35% of net self-employment earnings. The Social Security portion is limited by the annual wage base and the estimator accounts for W-2 Social Security wages that may already have used part of that limit.
Medicare tax is not subject to the Social Security wage cap, and Additional Medicare Tax can apply above the filing-status threshold. The estimator also shows the deductible employer-equivalent portion of self-employment tax. It does not calculate your complete federal income-tax return.
Self-employment tax is separate from regular federal income tax, which is why a freelancer's total federal liability can feel much larger than one headline percentage suggests. The Social Security portion is limited by the applicable wage base and may interact with wages from an employee job, while Medicare rules differ. Business expenses reduce net self-employment earnings before the calculation, so accurate bookkeeping matters just as much as the tax formula itself.
Frequently Asked Questions
Is self-employment tax simply 15.3% of business profit?
Not exactly. The 12.4% Social Security and 2.9% Medicare components generally apply to 92.35% of net self-employment earnings, with the Social Security component subject to the annual wage base.
Why does the calculator ask for W-2 wages?
W-2 Social Security wages can use part of the annual Social Security wage base, reducing the amount of self-employment earnings still subject to the 12.4% Social Security portion.
What if I have both W-2 wages and self-employment income?
The Social Security wage base applies across covered earnings, so wages can affect how much additional self-employment income is subject to the Social Security portion. Medicare rules have different thresholds.
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