Free tool
Self-Employment Tax Calculator
The Social Security and Medicare owed on business profit, which nobody is withholding for you — and which is separate from, and on top of, income tax.
Self-employment tax is the part that catches people out. An employee pays half of Social Security and Medicare and their employer pays the other half; work for yourself and you are both, so you pay both — 15.3% between them, on profit, before income tax has been considered at all.
This works it out, including the piece most calculators get wrong: if you also have a job, the Social Security ceiling is shared between the two incomes rather than applied to each.
Your numbers
Business income minus business expenses, for the year. Not your revenue, and not what you paid yourself.
From a job where Social Security and Medicare are already withheld. Leave blank if the business is your only income.
Only affects the 0.9% Additional Medicare tax, which starts above $200,000.
What you owe in self-employment tax
On $55,410 — self-employment tax applies to 92.35% of profit, not all of it.
No ceiling. Medicare is charged on every dollar of the base.
That is self-employment tax alone. Income tax comes on top of it, at your ordinary rate — the two are separate bills that arrive together.
Half of it comes back as a deduction. $4,239 of this reduces the income your income tax is calculated on. It does not reduce the self-employment tax itself, and it is applied automatically on a correctly prepared return.
2026 rates. Social Security 12.4% up to $184,500 of combined wages and self-employment income; Medicare 2.9% with no ceiling.
What this does not include
This is self-employment tax only — the Social Security and Medicare you owe because nobody is withholding them for you. It is not your total tax bill.
- Income tax. Federal and South Carolina, both charged on the same profit and neither shown here. The refund estimator puts them together.
- The QBI deduction, which can reduce the income tax on this profit but never the self-employment tax.
- Whether your expenses are complete. Self-employment tax is charged on profit, so every deduction you fail to record raises this figure. That is usually where the money is — the checklist for your trade is free.
- What you should be paying quarterly. This tax is not withheld, so it is normally paid in four instalments through the year. The quarterly calculator works out the instalment.
This is an estimate, not a tax return. It is a projection from the figures you entered, using published federal rates for the tax year shown. It is not a completed or filed return, it is not professional tax advice, and it does not create a client relationship. Your actual liability depends on your full circumstances and on documents this page never sees. Before acting on a number here — changing your withholding, setting an estimated payment, spending a refund — have it checked against your real situation. Call (864) 781-4035 or book a free consultation.
It applies to 92.35% of profit, not all of it
The calculation starts by taking 92.35% of net profit and charging the tax on that. The missing 7.65% stands in for the employer half that an employee’s wages never show — a rough adjustment to put a self-employed person on the same footing.
Then half of the resulting tax is deductible against income tax. It does not reduce the self-employment tax itself, and it happens automatically on a correctly prepared return. On an incorrectly prepared one it is quietly missed, which is one of the more common things a free review turns up.
The wage base is one ceiling, not one per job
Social Security stops at an annual wage base; Medicare does not stop at all. What people get wrong is that the ceiling covers everything you earn, not each source separately.
So an employee earning close to the ceiling who also runs a side business pays much less Social Security on the business profit than the headline rate suggests — sometimes none, if the salary has already used the ceiling up. Medicare is still charged on every dollar. Enter your wages in the second field and the calculator accounts for it.
Every missed expense raises this bill
Self-employment tax is charged on profit, so it is charged on every dollar of legitimate business cost you failed to record. At 15.3%, plus income tax on the same dollar, an unrecorded expense costs considerably more than its face value.
This is where the money usually is, and it is rarely exotic — vehicle and mileage, home office where it genuinely qualifies, equipment, supplies, insurance, retirement contributions. Mileage in particular needs records kept at the time, not reconstructed in April. The deduction checklists are written per trade and free.
Self-employment tax questions
Is self-employment tax the same as income tax?
No, and this is the misunderstanding that produces most surprise bills. They are separate charges on the same profit, and both are owed. Self-employment tax funds Social Security and Medicare; income tax is worked out on your bracket afterwards. The refund estimator shows the two together.
Do I owe it if I only made a little?
There is a small threshold below which it does not apply, but it is low — well below the point at which income tax starts. Most people who think they earned too little to owe self-employment tax are wrong about it, which is why a first 1099 so often produces an unexpected bill.
I did not get a 1099. Do I still report it?
Yes. The obligation attaches to the income, not to whether anyone sent you a form. Cash work, payments below a reporting threshold and platform income that generated no 1099 are all reportable, and all carry this tax. Self-employed tax services covers how it is put on the return.
Would an S-Corp reduce this?
It can, by splitting profit into a salary that carries payroll tax and a distribution that does not — but it costs money to run and below a certain profit the cost exceeds the saving. The S-Corp savings calculator shows both sides at your numbers.
How do I actually pay it?
Normally in four instalments through the year, because nothing is being withheld. Skipping them does not defer the tax, it adds penalties on top of it. The quarterly calculator works out the instalment.
Not the question you had? The full tax FAQ covers more ground, and our client reviews say what the work is actually like.
More on self-employed tax help
This tool supports our self-employed & freelancer taxes service.
A Guide to Filing Taxes as a Self-Employed Individual
Read articleQuarterly Estimated Taxes: A Complete Guide for SC Business Owners
Read articleSelf-Employment Tax Guide for South Carolina
Read articleFreelancer Tax Preparation in Greenville, SC
Read article1099 vs W-2: What Greenville Workers Need to Know
Read articleHome Office Deduction Guide for the SC Self-Employed
Read articleTell us what you need
Send a short note about your situation and we’ll come back to you with a straight answer — whether that’s a quote, a next step, or a referral if it isn’t something we handle.
Prefer to talk it through first? Book a consultation and we’ll find a time, in the Easley office or virtually.
Not sure which option is best for you?
Reach out to Elite Pro-Tax & Financial Services to discuss your tax and financial needs today.