How this is calculated
- Net earnings from self-employment. Self-employment tax isn't charged on
your full Schedule C profit — you first multiply it by 92.35% (this factor removes the
employer-half of FICA that a W-2 employee wouldn't be taxed on):
net earnings = profit × 0.9235. If net earnings come to less than$400, no self-employment tax is owed and you generally skip Schedule SE. - Social Security portion (12.4%). Applied only up to the 2026 Social
Security wage base of
$184,500, and that base is shared with any wages a W-2 job already taxed:SS = 12.4% × min(net earnings, $184,500 − W-2 SS wages), never below $0. Once you (across all jobs) hit the wage base, the 12.4% piece stops. - Medicare portion (2.9%). Medicare has no wage cap, so it applies to every
dollar of net earnings:
Medicare = 2.9% × net earnings. - Additional Medicare Tax (0.9%). An extra 0.9% above your filing-status
threshold —
$200,000single / head of household / qualifying surviving spouse,$250,000married filing jointly,$125,000married filing separately — applied to your net SE earnings combined with any W-2 wages, the way Form 8959 does:Add'l = 0.9% × max(net earnings + W-2 wages − threshold, 0). - Total and the deductible half.
SE tax = SS + Medicare + Additional Medicare. The effective rate isSE tax ÷ profit. You may deducthalf of the regular 15.3% SE tax(the SS + Medicare portions only — the Additional Medicare Tax is not deductible under IRC §164(f)) as an above-the-line adjustment to income on Schedule 1 — it lowers your income tax, not the SE tax itself, and you get it whether or not you itemize.
Estimating your total federal tax
Self-employment tax isn't the whole bill — you also owe federal income tax on the profit. The "estimated total federal tax" section near the top works it out with 2026 figures:
- Start from taxable income.
taxable income = net profit − ½ of SE tax − retirement contribution − QBI deduction − standard deduction, floored at $0. The deductible half of SE tax and any SEP-IRA / Solo 401(k) contribution both come off the top, the same way they do on Schedule 1. - QBI deduction (simplified). When the toggle is on, we subtract
20% × (net profit − ½ SE tax − retirement)for the Qualified Business Income deduction. This is the simplified version: the real Section 199A deduction is also capped at 20% of taxable income and phases out for specified service businesses above the 2026 income thresholds — neither of which is modeled here. - 2026 standard deduction.
$16,100single or married filing separately,$32,200married filing jointly (and qualifying surviving spouse),$24,150head of household. This estimate always uses the standard deduction, never itemized. - 2026 marginal brackets. Taxable income runs through the 2026 federal
brackets for your filing status (10% / 12% / 22% / 24% / 32% / 35% / 37%) to get the income
tax.
Total federal tax = income tax + SE tax, and the total effective rate istotal federal tax ÷ net profit.
Why the income-tax line is only an estimate: it assumes the self-employment profit is your only income, that you take the standard deduction, and that you claim no tax credits (child tax credit, education, EITC, saver's credit) and no other adjustments. Real returns often add a spouse's income, W-2 wages, investment income, itemized deductions, or credits — any of which moves the number. The SE-tax figures are exact Schedule SE math; the income-tax figures are planning-grade.
What this still doesn't model: tax credits of any kind, itemized deductions, S-corp reasonable-compensation splits, partnership/K-1 specifics, the Section 1256 or optional Schedule SE methods, the full Section 199A limits on the QBI deduction, self-employed health-insurance deductions, other household income, or state taxes. This estimator combines your W-2 wages with your net SE earnings for the Additional Medicare Tax threshold, the way Form 8959 does; it uses the W-2 Social Security wages you enter as a proxy for Medicare wages, which can differ above the Social Security wage base. The SE tax is a clean estimate of your Schedule SE liability and the income tax is a planning-grade estimate — together, not a filed return.
Data as of 2026 (tax year 2026). Social Security rate 12.4%, Medicare 2.9%, and Additional Medicare 0.9% are the statutory self-employment rates; the $184,500 Social Security wage base is the SSA's 2026 taxable maximum (up from $176,100 in 2025). Additional Medicare thresholds ($200,000 / $250,000 / $125,000) are set by statute and not inflation-indexed.
Frequently asked questions
What is the self-employment tax rate for 2026?
The self-employment tax rate is 15.3% — 12.4% for Social Security plus 2.9% for Medicare. It applies to your net earnings from self-employment, which are 92.35% of your Schedule C net profit. For 2026 the 12.4% Social Security portion only applies up to the $184,500 wage base; the 2.9% Medicare portion has no cap, and a 0.9% Additional Medicare Tax applies above $200,000 (single) or $250,000 (married filing jointly).
Why is only 92.35% of my profit taxed?
Employees split FICA with their employer, and the employer's half isn't taxed as the employee's wages. To put the self-employed on equal footing, the IRS lets you first multiply your net profit by 92.35% (that is, 100% minus half of the 15.3% rate) before applying the 15.3% self-employment tax. This 0.9235 factor is built into Schedule SE and is why your net earnings from self-employment are always a little lower than your bottom-line profit.
Can I deduct half of my self-employment tax?
Yes. You can deduct one-half of your self-employment tax as an above-the-line adjustment to income on Schedule 1 of Form 1040. It lowers your adjusted gross income and therefore your income tax — it does not reduce the self-employment tax itself, and you get it whether or not you itemize. This calculator shows that deductible half separately.
How do W-2 wages affect my self-employment tax?
Social Security tax stops at the annual wage base ($184,500 for 2026), counting both W-2 and self-employment earnings. If a job already paid Social Security tax on part of that base, only the leftover base is subject to the 12.4% Social Security portion of your SE tax; enter your W-2 Social Security wages to coordinate the cap. The 2.9% Medicare portion still applies to all of your net self-employment earnings because Medicare has no wage cap.
How much total tax will I owe on 1099 income?
On 1099 income you generally owe two federal taxes: self-employment (SE) tax — the full 15.3% Social Security + Medicare that a W-2 job would split with an employer — plus regular federal income tax on what's left after the deductible half of SE tax, any retirement contribution, the QBI deduction, and your standard deduction. As a rough rule, a single filer with only 1099 income often lands somewhere around 20–30% of net profit in combined federal tax once income climbs into the 22–24% brackets, but the exact figure depends on your deductions and credits. The "estimated total federal tax" section above works this out for your numbers — for example, $80,000 of net profit for a single filer comes to roughly $11,300 of SE tax plus about $4,960 of income tax, for about $16,260 total (a ~20% effective rate). Add your state's income tax on top, and remember to set aside for quarterly estimated payments.
This calculator is an educational estimate, not tax advice, not a filed return, and not a substitute for a licensed tax professional. The self-employment tax is computed from Schedule SE; the federal income tax shown is a rough planning estimate that assumes only this income and the standard deduction, with no tax credits, itemized deductions, other household income, S-corp compensation splits, or state taxes, and it does not account for every Schedule SE special method or the full Section 199A limits on the QBI deduction. No liability is accepted for decisions made from these results. Estimates only — consult a tax professional.