How much is self-employment tax on 1099 income?

Self-employment tax is Social Security and Medicare with both halves on you. An employee pays one half out of their check and never sees the other, which their employer pays. Work for yourself and you are both parties, so you owe the whole thing on Schedule SE, and it arrives on top of income tax rather than instead of it.

It does not apply to your profit directly. Under § 1402(a)(12), net earnings from self-employment are 92.35% of net profit, the rough equivalent of the employer half an employee never has in their wages: $80,000 of profit is $73,880 of net earnings. The 15.3% rate applies to that, producing $11,304. Then half of it, $5,652, comes straight back off your income on Form 1040 line 10 under § 164(f), which is the second thing most calculators approximate and this one takes off the return.

Income tax then runs on what is left. Adjusted gross income is $74,348, the single standard deduction takes $15,750, the qualified business income deduction takes $11,720, and $46,879 of taxable income produces $5,387 of income tax. Add the two halves and the year costs $16,691 on $80,000 of work, or 22.4% of adjusted gross income. The calculator above shows every one of those lines, numbered the way the forms number them, so you can hold it against your own return.

The advice everyone gives is to save 30% and hope. Here is what the returns actually say, filing single with no job on the side. Each row is a full computed return, not a rate applied to a number.

The set-aside column climbs from 16.5% at $25,000 to 26.4% at $200,000, because self-employment tax is flat while income tax is not. So 30% overshoots at the bottom of the table by $3,370 and still has room to spare at the top. Saving too much is a cash-flow problem rather than a penalty, which is why the rule survives, but it is not free when you are the one waiting on the money.

It fails the other direction too. Take $80,000 of freelance profit earned by someone who also holds a job paying $176,100. The profit only costs $2,143 of self-employment tax, because the job already used the Social Security wage base, but it stacks on top of a salary in higher brackets, so the real cost of that side income is $24,894, or 31.1%. Set aside 30% and you are $894 short in April. This is why the number belongs to your return and not to a rule of thumb.

15.3% is the rate, and it is real: 12.4% for Social Security under § 1401(a) and 2.9% for Medicare under § 1401(b). Almost nobody pays that share of their profit, and the gap is not rounding.

At $80,000 of profit the raw multiplication would be $12,240. The actual Schedule SE line 12 is $11,304, because the rate applies to $73,880 of net earnings rather than the full profit. Then $5,652 of it is deducted against income tax, which at these brackets hands back part of it again. That is why the measured cost of the next $1,000 of profit here is 23.1% rather than 15.3% plus a bracket: the calculator computes the return twice and takes the difference, so every interaction between the two taxes is in the number.

The Social Security half is capped. Once combined W-2 wages and net earnings reach $176,100 for 2025, that 12.4% stops, and only the 2.9% Medicare half keeps running, with no ceiling at all. For someone with no job on the side, net earnings reach the cap at $190,688 of net profit.

You can watch it happen. Take $190,688 of profit against $189,688: the extra $1,000 costs $141.25 of self-employment tax. Go from $190,688 to $191,688, one thousand dollars further, and the same step costs $26.78. The bill keeps rising after that, but through income-tax brackets. If you cross the line partway through the year, quarterly estimates built on the first quarter will overshoot the rest, which is a good problem and worth knowing about.

One thing does keep climbing above the cap. The additional Medicare tax under § 3101(b)(2) adds 0.9% on earnings above a threshold set by filing status, it is not withheld from a 1099, and no one sends a notice about it. When your numbers cross it, the calculator names the amount in a warning rather than folding it silently into the total.

Section 199A lets most self-employed people deduct up to 20% of qualified business income from taxable income. Worth $2,414 at the inputs above: $16,691 with it against $19,105 without. The deduction shown is $11,720, not 20% of $80,000, because Form 8995 applies two limits and takes the lower. Qualified business income is profit after the deductible half of self-employment tax comes out, so 20% of it is $14,870. The deduction is also capped at 20% of taxable income before the deduction, which is $11,720 here. The second one binds, and it is the answer. Getting there needs two passes of the return: the first produces the deductible half, and the second feeds the reduced amount back in.

Above a taxable-income threshold, $197,300 for single filers in 2025, the simple version stops applying. Above that line the deduction needs Form 8995-A, which depends on facts this calculator does not collect: whether the business is a specified service trade or business, the W-2 wages the business paid, and the unadjusted basis of its property. The engine refuses to guess, so the answer above the threshold is the tax with no qualified business income deduction at all. Treat it as a ceiling, not the number you will file.

That is not a hypothetical limit, it is what the page does. At $276,000 of profit filing single, the answer with the deduction requested and the answer with it switched off are the same number, $85,389, and a warning says why. A calculator that quietly returned 20% of profit there would be off by thousands in the direction you would rather not discover in April.

State and local tax. Nine states charge no income tax, the rest run from a low flat rate to double digits, and several cities charge their own on top. Some states also charge business or gross-receipts taxes on the same profit. Nothing on this page includes any of it.

Deductions a self-employed person usually has. A solo 401(k) or SEP-IRA contribution, the self-employed health insurance deduction, half of the home office, business losses carried in from another year, and itemized deductions all change the answer and none of them is an input here. Every one of them pushes the real bill down, so treat this as the number before your own deductions rather than after them. Dependents are not modelled either, which means no child tax credit and no earned income credit.

Last year's return. The safe harbor this page uses is 90% of the current year's tax, $3,755 per installment across 4 installments here, because that rule needs only the year you are in. The other safe harbor, 100% of last year's tax or 110% if you earned more than a threshold, is often the easier one to hit and this calculator cannot check it, because it never sees last year. Everything here is federal tax for 2025 on nonfarm self-employment income: the parameter set is the current year, not a history of past rates, and none of it is tax advice.

This calculator is built to be used without a browser. Every input is a query parameter on this page, and the same parameters on the JSON twin return the complete answer as a document.

GET /tools/self-employment-tax.json?net=120000&status=married-joint&wages=40000

The response carries inputs after parsing and clamping, result with self-employment tax, the income tax on top of it, total federal tax, net earnings, the deductible half, the qualified business income deduction and whether Form 8995-A was required, the set-aside rate and the quarterly amount, the safe-harbor installment, the effective and measured marginal rates, plus scheduleSe and form1040, the numbered lines the answer is built from, parameters, the Schedule SE rates and wage base measured out of the engine, and sensitivity across a profit ladder, all five filing statuses, and both § 199A settings, drivers ranked by effect with a plain sentence each, assumptions that say for every field whether you supplied it and name the source when the default came from one, sources with a URL and an as-of date for each source the tool cites, which is an empty list on the calculators whose every default is an example input rather than a published figure, warnings, a disclaimer, and in tool the canonicalUrl and jsonUrl that carry only your non-default parameters. The canonical URL is the answer's permanent address; use it when you cite the number.

Parameters, all optional, in any order:

• net ($ per year), default $80,000 per year.
• wages ($ per year), default $0 per year.
• withholding ($ per year), default $0 per year.
• safeHarbor (%), default 90%, from IRS Publication 505, Tax Withholding and Estimated Tax.
• status (one of single, married-joint, married-separate, head-of-household, qualifying-surviving-spouse), default single.
• qbi (one of yes, no), default yes: whether to claim the § 199A deduction.

Values accept plain numbers and loose human formats such as 100k, $100,000, or 6.5%. Unknown parameters are ignored, values outside a field's range are clamped and reported in warnings, and the endpoint never fails on bad input. Responses are cacheable for a day; the defaults change when their sources publish, and tool.version changes when the method does.

• IRS Rev. Proc. 2024-40 (2025 inflation-adjusted items), as of 2025-01-01. The rate tables, standard deduction, and the qualified business income threshold for tax year 2025, as published by the IRS.
• One Big Beautiful Bill Act (P.L. 119-21), as of 2025-07-04. The statute that sets the current standard deduction used for 2025.
• 26 U.S.C. (Internal Revenue Code), as of 2025-01-01. The code sections the calculation implements: § 1401 self-employment tax, § 1402 net earnings, § 164(f) the deductible half, § 199A the qualified business income deduction, § 3101(b)(2) additional Medicare tax.
• IRS Publication 505, Tax Withholding and Estimated Tax, as of 2025-01-01. The estimated-tax rules under 26 U.S.C. § 6654: four installments across the year, and the 90% of this year's tax safe harbor that avoids an underpayment penalty.

The first three are the parameter authorities the engine itself reports for every computation, not citations chosen after the fact: the rate tables and thresholds come from the IRS revenue procedure and the statute that set them, and the code sections are the rules the calculation implements. The publication is cited for one thing only, the share of the year's tax that has to be paid in to avoid an underpayment penalty, which is the default in the advanced inputs.

Carlo is a personal finance agent. It knows your accounts, debts, and goals, so instead of a worked example at the profit you typed it can watch what you actually invoice and set aside through the year, and tell you in March whether the quarter you skipped is going to cost you. Text it the question.

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