Glossary term

Self-Employment Tax

Self-employment tax is the Social Security and Medicare tax paid by people who work for themselves and have net earnings from self-employment.

Updated

May 19, 2026

Read time

3 min read

What Is Self-Employment Tax?

Self-employment tax is the Social Security and Medicare tax paid by people who work for themselves. It applies to net earnings from self-employment, not simply to gross receipts.

Employees usually split Social Security and Medicare taxes with an employer through payroll withholding. Self-employed people generally pay both the worker and employer portions themselves, which is why the tax can feel larger than ordinary income-tax withholding.

Key Takeaways

  • Self-employment tax funds Social Security and Medicare.
  • It generally applies when net earnings from self-employment reach the IRS threshold.
  • It is separate from regular federal income tax.
  • Taxpayers calculate it on Schedule SE and may deduct one-half of it when figuring adjusted gross income.

How Self-Employment Tax Works

Self-employment tax is based on net earnings from a trade or business. A sole proprietor, independent contractor, partner, or member of certain LLCs may have income subject to the tax. Ordinary and necessary business expenses reduce gross income before net earnings are determined.

The tax includes a Social Security portion and a Medicare portion. The Social Security portion applies only up to an annual wage base, while the Medicare portion generally applies to all net earnings. An additional Medicare tax can apply above certain income thresholds.

Where It Shows Up

Tax Item

Purpose

Schedule C

Often used to report sole proprietor business income and expenses

Schedule SE

Used to calculate self-employment tax

Form 1040

Reports the overall federal tax return result

Estimated tax payments

Can help cover income tax and self-employment tax during the year

Cash Flow Impact

Self-employment tax often surprises new freelancers and business owners because client payments do not arrive with payroll taxes already withheld. The gross amount deposited into a bank account is not all spendable income.

Estimated tax payments can help spread the cost through the year. Without enough withholding or estimated payments, a taxpayer may face a large balance due and possible penalties when filing the annual return.

Common Misunderstandings

Self-employment tax is not the same as income tax. A person can owe both. It also does not disappear just because a business is part-time, gig-based, or paid through a platform.

Another common mistake is focusing only on revenue. The tax is generally based on net earnings, so accurate expense records matter. At the same time, not every personal cost is a deductible business expense, and aggressive deductions can create audit and cash-flow problems.

The Bottom Line

Self-employment tax is the Social Security and Medicare tax attached to working for yourself. It should be built into pricing, cash reserves, bookkeeping, and estimated tax planning rather than treated as a surprise at filing time.

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