Self-Employment Tax for LLC Owners, Explained
Self-employment tax is the Social Security and Medicare tax that self-employed people pay on their business earnings. The rate is 15.3%, and it applies on top of income tax. If you have only ever been an employee, this is the number that makes your first year of LLC profit feel much smaller than expected — because as an employee, your employer was quietly paying half of it for you.
What the 15.3% is made of
The rate breaks into 12.4% for Social Security and 2.9% for Medicare. As an employee you pay 7.65% and your employer pays the matching 7.65%. When you work for yourself you are both parties, so you pay the full 15.3%.
The Social Security portion applies only up to an annual wage base that the IRS adjusts each year; earnings above it are not subject to the 12.4%. The Medicare portion has no cap, and an additional 0.9% Medicare tax applies to earnings above $200,000 for single filers or $250,000 for married filing jointly.
What it applies to
Self-employment tax applies to your net earnings from self-employment — business profit after deductible expenses, not gross revenue. Every legitimate business deduction you take reduces both your income tax and your self-employment tax.
For a default-taxed LLC, it generally applies to your entire share of active business profit, regardless of how much you actually withdrew. Passive income such as most rental income is typically not subject to it, and neither are distributions from an LLC taxed as an S-Corporation.
One partial offset: you can deduct half of your self-employment tax when computing your adjusted gross income. It does not reduce the self-employment tax itself, but it lowers your income tax.
Quarterly estimated payments
Nobody withholds taxes from your business profit, so the IRS expects you to pay as you go. Estimated payments are generally due four times a year — around April 15, June 15, September 15, and January 15 of the following year — covering both income tax and self-employment tax.
Underpaying triggers penalties even if you settle up in April. A common rule of thumb is to set aside 25–30% of every profit dollar in a separate account as it comes in, then pay quarterly from that account. Run your own numbers with the Self-Employment Tax Calculator rather than relying on a rule of thumb alone.
How to legitimately reduce it
Deduct everything you are entitled to. Home office, health insurance premiums, retirement contributions, equipment, software, and mileage all reduce net earnings and therefore the tax. Sloppy expense tracking is expensive twice over.
Once profits are consistently high, the S-Corp election becomes the main lever. It lets you take part of your income as a reasonable salary (subject to payroll taxes) and the rest as distributions (not subject to self-employment tax). The tradeoff is payroll processing, a separate business return, and higher accounting fees — which is why it usually only makes sense above roughly $40,000–$60,000 of consistent net profit.
It is worth remembering what the tax buys: Social Security credits toward your future retirement and disability benefits. Aggressively minimizing your reported earnings also minimizes what you will eventually collect.
Key takeaways
- Self-employment tax is 15.3% — 12.4% Social Security plus 2.9% Medicare — paid on top of income tax.
- You pay both halves because you are both employer and employee.
- It applies to net business profit after deductions, not gross revenue, and not to what you withdrew.
- The Social Security portion stops at an annual wage base; Medicare has no cap, plus 0.9% above $200k/$250k.
- Pay quarterly estimates, deduct thoroughly, and consider an S-Corp election at consistently higher profits.
Try the tool
Self-Employment Tax Calculator