If you work for an employer, you pay 7.65% in FICA taxes (Social Security and Medicare) and your employer pays an equal 7.65% on your behalf. When you are self-employed, there is no employer — so you pay both halves: 15.3% in self-employment (SE) tax. This often catches new freelancers and business owners off guard.
What Self-Employment Tax Covers
Self-employment tax is not income tax. It is the self-employed person’s version of FICA — the payroll tax that funds Social Security and Medicare:
| Component | Rate |
|---|---|
| Social Security | 12.4% (on income up to the wage base) |
| Medicare | 2.9% (on all self-employment income) |
| Total SE Tax | 15.3% |
In 2025, the Social Security wage base is $176,100. The 12.4% Social Security portion only applies to the first $176,100 of net self-employment income. The 2.9% Medicare portion has no cap.
Above $200,000 in net self-employment income (single filer), an additional 0.9% Additional Medicare Tax applies, bringing the Medicare rate to 3.8% on income above that threshold.
How Net Self-Employment Income Is Calculated
Self-employment tax is based on net earnings from self-employment, not gross revenue. Net earnings equal gross business income minus allowable business expenses (reported on Schedule C).
There is one more adjustment: the IRS allows you to reduce net earnings by 92.35% before applying the SE tax rate. This reflects the fact that employees pay Social Security and Medicare on wages that have already been reduced by the employer’s share of FICA — a subtle parity adjustment.
$$\text{Net SE Earnings} = \text{Schedule C Net Profit} \times 92.35%$$
$$\text{SE Tax} = \text{Net SE Earnings} \times 15.3%$$
For example, if your Schedule C net profit is $80,000:
- Net SE earnings: $80,000 × 92.35% = $73,880
- SE tax: $73,880 × 15.3% = $11,304
The Deductible Half of SE Tax
One of the few tax breaks for the self-employed: you can deduct half of the SE tax from gross income as an above-the-line deduction on Schedule 1 of Form 1040. This deduction reduces your adjusted gross income (AGI) and therefore your income tax — but it does not reduce the SE tax itself.
From the example above:
- SE tax: $11,304
- Deductible half: $11,304 ÷ 2 = $5,652
This $5,652 reduces your AGI before income tax is calculated, effectively recovering some of the SE tax cost.
Schedule SE: The Form You File
Schedule SE is where you calculate self-employment tax and report it on your Form 1040. It is a straightforward form:
- Start with net profit from Schedule C (or other self-employment income)
- Multiply by 92.35% to get net earnings from self-employment
- Apply 15.3% (or 2.9% on the portion above the Social Security wage base)
- Divide by 2 to get the deductible portion
The total SE tax flows to Schedule 2 (Additional Taxes) and then to your Form 1040. The deductible half flows to Schedule 1 (Adjustments to Income).
SE Tax vs. W-2 FICA: The Key Differences
| Feature | W-2 Employee | Self-Employed |
|---|---|---|
| Social Security rate | 6.2% (employee only) | 12.4% (both halves) |
| Medicare rate | 1.45% (employee only) | 2.9% (both halves) |
| Employer’s share | Paid by employer | Paid by you |
| FICA on gross wages | Yes, from first dollar | After Schedule C deductions |
| Deduction available | None | Half of SE tax is deductible |
| Withholding | Automatic | Must pay via estimated taxes |
The key structural difference: a W-2 employee never sees the employer’s 7.65% contribution — it comes on top of their wages. A self-employed person’s gross revenue must effectively cover both the worker and employer shares.
Worked Example: Full Tax Calculation
Suppose you are a single freelancer with $100,000 in gross business revenue and $15,000 in allowable business expenses.
Step 1: Net profit (Schedule C) $100,000 − $15,000 = $85,000
Step 2: Net SE earnings $85,000 × 92.35% = $78,498
Step 3: SE tax $78,498 × 15.3% = $12,010
Step 4: Deductible half $12,010 ÷ 2 = $6,005
Step 5: Adjusted Gross Income $85,000 − $6,005 = $78,995
Step 6: Taxable income (after 2025 standard deduction of $15,750) $78,995 − $15,750 = $63,245
Step 7: Federal income tax (2025 single brackets)
- 10% on $11,925 = $1,192.50
- 12% on $36,550 = $4,386.00
- 22% on $14,770 = $3,249.40
- Total income tax: $8,828
Total federal tax burden:
- SE tax: $12,010
- Income tax: $8,993
- Combined: $20,993 (approximately 24.7% of gross revenue, or 20.9% of gross revenue after expenses)
Self-Employed Retirement Deductions
One of the most effective ways to reduce the SE tax burden is to contribute to a self-employed retirement plan, which reduces both income tax and, in some cases, the base for self-employment tax calculations:
- SEP-IRA: Contribute up to 25% of net self-employment income (after SE tax deduction), up to $70,000 in 2025
- Solo 401(k): Employee contributions of up to $23,500 plus employer contributions of up to 25% of net SE income; total cap of $70,000
- SIMPLE IRA: For businesses with employees; lower contribution limits
Contributions to a SEP-IRA or Solo 401(k) reduce AGI and therefore income tax. They do not reduce SE tax directly, since SE tax is computed before retirement contributions are deducted — but the tax savings are still substantial.
Self-Employed Health Insurance Deduction
If you pay for your own health, dental, or vision insurance (and are not eligible for employer-sponsored coverage through a spouse), the premiums are 100% deductible as an above-the-line deduction. Like the SE tax deduction, this reduces AGI without itemizing.
Estimated Tax Payments
Because no employer withholds taxes from self-employment income, you must pay federal taxes quarterly using Form 1040-ES. The 2025 due dates are:
- April 15 (Q1: January–March)
- June 16 (Q2: April–May)
- September 15 (Q3: June–August)
- January 15, 2026 (Q4: September–December)
Underpaying can trigger an underpayment penalty. The safe harbor rules (paying at least 100% of last year’s tax, or 110% if prior-year AGI exceeded $150,000) protect you from penalties even if your actual liability turns out higher.
Key Takeaways
- Self-employment tax is 15.3% — both the employee and employer shares of Social Security (12.4%) and Medicare (2.9%).
- SE tax is calculated on 92.35% of Schedule C net profit, not gross revenue.
- You can deduct half of SE tax as an above-the-line deduction, reducing your income tax.
- File Schedule SE to calculate the amount; report the total on Schedule 2.
- Retirement plan contributions (SEP-IRA, Solo 401k) significantly reduce income tax on self-employment earnings.
- Quarterly estimated tax payments are required to avoid underpayment penalties.