Updated 30 March 2026
Self-Employed Social Security Tax
Self-employed workers pay the full 12.4% Social Security tax rate (both the employee and employer portions) but get to deduct half. Here is exactly how it works.
The 12.4% Self-Employment Tax
When you work for an employer, you each pay 6.2% of your wages toward Social Security. As a self-employed individual, there is no employer to pick up half the tab. You are responsible for the full 12.4% through the self-employment tax, reported on Schedule SE of your federal tax return.
The self-employment tax covers both Social Security (12.4%) and Medicare (2.9%), for a combined rate of 15.3%. This page focuses on the Social Security portion only. The Medicare portion has no wage base limit, so you pay 2.9% on all net self-employment income regardless of amount.
The 92.35% Rule
You do not pay self-employment tax on 100% of your net earnings. Instead, the IRS allows you to multiply your net self-employment income by 92.35% (which equals 100% minus 7.65%). This adjustment accounts for the fact that W-2 employers do not pay FICA on the employer share of FICA taxes.
Formula:
Taxable SE base = Net self-employment income x 0.9235
Social Security tax = Taxable SE base x 0.124 (up to wage base of $168,600)
The 50% Deduction
After calculating your self-employment tax, you can deduct half of it as an above-the-line deduction on your Form 1040. This means you get the deduction whether you itemize or take the standard deduction. It reduces your adjusted gross income (AGI), which can lower your income tax, qualify you for other deductions, and reduce your overall tax burden.
The deduction is for income tax purposes only. It does not reduce the self-employment tax itself. You still pay the full 12.4% Social Security tax on your taxable base; you just get to deduct half of it when calculating your income tax.
Step-by-Step Calculation
Calculate net self-employment income
Total business revenue minus all deductible business expenses (Schedule C line 31)
Multiply by 92.35%
This gives you the taxable SE base. If net income is $100,000, the base is $92,350
Cap at the wage base limit
If your taxable base exceeds $168,600, only $168,600 is subject to the 12.4% Social Security portion. The Medicare portion (2.9%) still applies to the full amount.
Apply the 12.4% rate
Multiply the capped taxable base by 12.4% to get your Social Security tax
Deduct half on your 1040
Take 50% of the total SE tax (including Medicare portion) as an above-the-line deduction
Examples at Different Income Levels
| Net SE Income | Taxable Base (92.35%) | SS Tax (12.4%) | 50% Deduction | Effective Rate |
|---|---|---|---|---|
| $50,000 | $46,175 | $5,726 | $2,863 | 11.45% |
| $100,000 | $92,350 | $11,451 | $5,726 | 11.45% |
| $168,600 | $155,723 | $19,310 | $9,655 | 11.45% |
| $200,000 | $168,600 | $20,906 | $10,453 | 10.45% |
| $300,000 | $168,600 | $20,906 | $10,453 | 6.97% |
Effective rate = SS tax divided by net SE income. Higher earners above the wage base see a lower effective rate because the tax is capped. Examples show Social Security portion only (12.4%), not the Medicare portion (2.9%).
Tips for Self-Employed Workers
- 1.Pay quarterly estimated taxes. The IRS expects self-employment tax to be paid in four installments (April 15, June 15, September 15, January 15). Missing these deadlines triggers underpayment penalties.
- 2.Maximize business deductions. Every dollar of legitimate business expense reduces your Schedule C income, which directly reduces your SE tax base.
- 3.Consider an S-Corp election. S-Corp owners pay themselves a reasonable salary (subject to FICA) and take remaining profits as distributions (not subject to SE tax). This can save significant SE tax at higher income levels.
- 4.Do not forget the deduction. The 50% SE tax deduction on Form 1040 line 15 is easy to overlook if you prepare your own taxes. Make sure you claim it.