Self-Employment Tax Calculator
Calculate the self-employment (SE) tax owed on your net freelance or business income, accounting for deductions and estimated payments already made. Used by sole proprietors and gig workers at tax time.
About this calculator
Self-employed individuals pay both the employee and employer share of FICA taxes, totaling 15.3% (12.4% Social Security + 2.9% Medicare). However, you only pay SE tax on 92.35% of net earnings—this adjustment accounts for the employer-equivalent deduction. The formula is: SE Tax = (Net Earnings − Business Deductions) × 0.9235 × 0.153 − Quarterly Payments Made. The 0.9235 multiplier exists because employees do not pay Social Security and Medicare on the employer's matching contribution, so the IRS grants self-employed taxpayers the equivalent reduction. You can also deduct half of your SE tax from gross income on Form 1040, further reducing your income tax. Net earnings above $168,600 (2024) are exempt from the 12.4% Social Security portion but still subject to the 2.9% Medicare tax.
How to use
Suppose your net self-employment earnings are $80,000, business deductions total $10,000, and you have made $2,000 in quarterly estimated payments. Step 1: Net after deductions = $80,000 − $10,000 = $70,000. Step 2: Apply the 92.35% adjustment: $70,000 × 0.9235 = $64,645. Step 3: Apply the 15.3% SE tax rate: $64,645 × 0.153 = $9,890.69. Step 4: Subtract payments made: $9,890.69 − $2,000 = $7,890.69 remaining SE tax due.
Frequently asked questions
Why do self-employed people pay more Social Security and Medicare tax than regular employees?
Regular employees only pay half of FICA taxes (7.65%), with their employer covering the other half. Self-employed individuals have no employer, so they are responsible for both the employee and employer portions, totaling 15.3%. To partially offset this burden, the IRS allows self-employed taxpayers to deduct half of the SE tax (the employer-equivalent portion) from their gross income when calculating income tax. This deduction does not reduce SE tax itself but does lower the income tax owed.
How do quarterly estimated tax payments affect my self-employment tax bill?
Self-employed individuals are required to pay taxes throughout the year via quarterly estimated payments, due in April, June, September, and January. These payments cover both income tax and self-employment tax. When you file your annual return, any estimated payments already made are credited against your total tax liability. If you underpay, you may owe a penalty; if you overpay, you receive a refund. This calculator subtracts your payments made to show only the remaining balance due.
What business deductions can reduce my self-employment tax base?
Business deductions that directly reduce your net self-employment earnings also reduce the base on which SE tax is calculated. Eligible deductions include home office expenses, vehicle mileage, equipment and software, professional subscriptions, and health insurance premiums (deducted separately on Form 1040). Retirement contributions to a SEP-IRA or Solo 401(k) reduce your income tax but do not reduce the SE tax base. Maximizing legitimate business deductions is one of the most effective ways to lower your overall SE tax liability.