Self Employment Tax Calculator
Calculate your self-employment tax for Social Security and Medicare. Includes the deductible portion and estimated quarterly payment amounts.
Business Income Information
Self Employment Tax
Estimated Quarterly Payments
If you need to pay quarterly estimated taxes, each payment would be approximately:
How Self Employment Tax Works
What is Self Employment Tax?
Self-employment tax covers Social Security and Medicare taxes for people who work for themselves. It's the equivalent of FICA taxes that employees and employers pay.
- Social Security: 12.4% on first $168,600 of combined income (2024)
- Medicare: 2.9% on all self-employment income
- Additional Medicare: 0.9% on income over $200,000 (single) or $250,000 (married)
Self Employment Tax Deduction
You can deduct 50% of your self-employment tax from your taxable income. This deduction is taken on your Form 1040 and reduces your adjusted gross income (AGI).
Quarterly Estimated Taxes
If you expect to owe $1,000 or more in taxes, you should make quarterly estimated tax payments. Due dates are typically:
- Q1: April 15
- Q2: June 15
- Q3: September 15
- Q4: January 15 (of following year)
Frequently Asked Questions
You must pay self-employment tax if you have net earnings of $400 or more from self-employment. This includes freelancers, independent contractors, sole proprietors, and partners in partnerships.
Yes! Business expenses are deducted from your gross income to arrive at net business income. Only your net income is subject to self-employment tax. Common deductions include home office, equipment, supplies, mileage, and professional services.
If you have W-2 income, your employer already pays half of FICA taxes. The Social Security wage base limit ($168,600 for 2024) applies to combined W-2 and self-employment income. If your W-2 income exceeds this limit, you won't owe Social Security tax on self-employment income.
About the Self Employment Tax Calculator
Self-employed workers pay 'self-employment tax' — both halves of FICA, since you're both employer and employee. This adds 15.3% on top of federal and state income tax. This page covers the calculation, the deductions you can take, and the quarterly estimated payments that keep you out of penalty.
The Formula
SE tax = Net SE income × 92.35% × 15.3% (12.4% Social Security up to $168,600 wage base + 2.9% Medicare on all). Half of SE tax (the 'employer half') is deductible on your federal return.
Worked Example
$80,000 self-employment net income. SE tax base: $80,000 × 0.9235 = $73,880. SE tax: $73,880 × 0.153 = $11,304. Half deductible: $5,652. Plus federal income tax on $80,000 − $5,652 deduction = $74,348 (some portion).
Quarterly estimated taxes
If you'll owe more than $1,000 in tax, pay quarterly: April 15, June 15, September 15, January 15. Use Form 1040-ES. Pay at least 90% of current-year tax or 100-110% of prior-year tax (110% if AGI over $150k) to avoid penalty.
Deductions that lower SE tax
Business expenses (mileage, home office, supplies, equipment), retirement contributions (SEP-IRA, Solo 401k), and health insurance premiums all reduce net SE income — and therefore SE tax.
Solo 401(k) vs SEP-IRA
Solo 401(k) allows both employee deferrals ($23,500) and employer profit-sharing (up to 25% of net SE income). SEP-IRA is simpler but only the profit-sharing portion. For most self-employed earners, Solo 401(k) allows higher contributions.
Common Mistakes
- Forgetting to pay quarterly estimates. The penalty is moderate but compounds annually.
- Mixing personal and business expenses. Keep a separate bank account.
- Not deducting home office. The simplified method ($5/sq ft up to 300 sq ft) is easy and often worth more than nothing.
Frequently Asked Questions
Can I deduct mileage to client sites?
Yes. 67¢/mile in 2024. Keep a log. Commute from home to your regular business location isn't deductible.
Do I need to form an LLC?
Not for tax purposes — LLCs don't change SE tax by themselves. They provide liability protection.
This calculator is for informational purposes only and does not constitute financial, tax, or legal advice. Consult a licensed professional before making significant financial decisions.