Self-employment tax calculator
Social Security and Medicare contributions on self-employed profit, with the deductible portion separated.
Self-employment tax
Estimate$11,304
15.3% on 73,880 of net earnings, half of it deductible
- Social Security portion
- $9,161.12
- Medicare portion
- $2,142.52
- Deductible half
- $5,651.82
| Net profit | $80,000 |
|---|---|
| Net earnings (92.35%) | $73,880 |
| Social Security 12.4% | -$9,161.12 |
| Medicare 2.9% | -$2,142.52 |
| Total | -$11,304 |
- This is on top of federal income tax, not instead of it.
The combined 15.3% applies to 92.35% of profit, and half of the resulting tax is deductible against income tax.
How this is calculated
How this is calculated
Self-employed pay both halves
Where an employee and employer split social contributions, a sole trader pays both. In the US that is 15.3% against 92.35% of profit — $11,304 on $80,000 — versus 7.65% for an employee.
tax = profit × 0.9235 × 15.3%Contribution ceilings are shared across income
Wages from a job and profit from a business count against one annual ceiling — $184,500 in the US. A $150,000 salary leaves only $34,500 of headroom, so most of the profit escapes the capped 12.4% component.
capped earnings = min(net earnings, ceiling − wages)Part of it is deductible
Half the tax reduces taxable income — about $5,652 of the $11,304 charged on $80,000 of profit — so the effective cost sits below the headline rate. This is separate from, and on top of, income tax.
deduction = tax ÷ 2Worked example: $80,000 of net profit
| Net profit | $80,000 |
|---|
| Charged on | $73,880 |
|---|---|
| Combined rate | 15.3% |
Social contribution rates and ceilings for the self-employed differ by country. Pick a country above for figures you can file against.
What this assumes
- Sole trader with profit net of expenses.
- No company salary split.
- Social contributions only, not income tax.
- Full-year trading.
Where this commonly goes wrong
- Self-employed contributions are rarely withheld, so the first profitable year usually arrives as one large bill.
- A loss year typically earns no state-pension credit even though it costs nothing.
- Combining employment and self-employment can over-collect against a shared ceiling, recoverable only at filing.
Questions
Why do the self-employed pay more social contributions?
They cover both the employee and employer share. In the US that is 15.3% against an employee 7.65%, though roughly half the difference comes back as a deduction against income tax.
Does a salaried job change what my business owes?
Usually yes. Wages generally fill any annual contribution ceiling first, so only the remaining headroom of your profit is charged the capped portion. Uncapped components still apply to all of it.
Is this instead of income tax?
No, it is on top. Social contributions and income tax are separate charges with different bases, and budgeting for only one leaves a large shortfall at filing. On $80,000 of profit the contributions alone are around $11,304.
When is it due?
Usually in instalments during the trading year rather than in one payment at filing. US sole traders pay quarterly estimates in April, June, September and January, and paying late attracts an underpayment penalty even if the full amount arrives eventually.
Is any of it deductible?
In the US half the 15.3% comes off adjusted gross income as an above-the-line deduction — roughly $5,652 on $80,000 of profit. The 0.9% surtax on high earners is excluded, so the deductible share falls slightly below half at large profits.
Related tools
Sources
Estimate only, based on published IRS figures for the current period. Not tax or legal advice. Confirm your position with the IRS, a CPA, or an enrolled agent.
T1