Self-Employed Tax Calculator
If you're a freelancer, independent contractor, or self-employed professional, understanding your tax obligations is essential for financial planning. This self-employed tax calculator estimates your self-employment tax (Social Security and Medicare), federal income tax, and quarterly estimated payments. Enter your total business income and deductible expenses to see how much you may owe. The calculation applies the 92.35% taxable base, the 15.3% SE tax rate, and the deduction for one-half of SE tax before computing income tax.
How This Calculation Works
Net self-employment income is calculated by subtracting business expenses from gross income. The SE tax base is 92.35% of net income, and the SE tax rate is 15.3% (12.4% Social Security + 2.9% Medicare). Half of the SE tax is deductible for income tax purposes. Federal income tax is then calculated on the adjusted taxable income using 2026 brackets. Quarterly estimated payments are the total annual tax divided by four.
How Self-Employment Tax Works in 2026
Self-employment tax replaces the payroll tax an employer would otherwise share with you. It is 15.3% in total: 12.4% for Social Security and 2.9% for Medicare, charged on 92.35% of net earnings from self-employment. The 92.35% adjustment exists to mirror the deduction an employer receives for its own share.
| Component | Rate | 2026 limit |
|---|---|---|
| Social Security | 12.4% | Applies up to $184,500 of combined wages and SE income |
| Medicare | 2.9% | No cap |
| Additional Medicare | 0.9% | Income above $200,000 single / $250,000 joint |
| Deductible portion | 50% of SE tax | Above-the-line deduction on Form 1040 |
Self-employment tax is separate from income tax and is not reduced by the standard deduction or by most tax credits. It is the reason a self-employed person with $60,000 of profit can owe over $8,000 before a single dollar of income tax is calculated.
The Three Deductions Every Self-Employed Person Should Use
1. Half of self-employment tax
Automatic on Form 1040 — it reduces adjusted gross income, which in turn can improve eligibility for IRA contributions, education credits and marketplace health subsidies.
2. Self-employed health insurance deduction
Premiums for you, your spouse and dependents are deductible above the line, up to your net self-employment profit. It reduces income tax but not self-employment tax, and it cannot be claimed for months when you were eligible for an employer plan through a spouse.
3. Qualified business income (QBI) deduction
Up to 20% of qualified business income, subject to taxable-income thresholds and limitations for specified service trades at higher incomes. On $80,000 of profit this can remove roughly $16,000 from taxable income without spending anything.
Retirement Accounts Built for the Self-Employed
These plans are the largest legal lever a profitable self-employed person has over their tax bill.
| Plan | Roughly how much you can contribute | Best for |
|---|---|---|
| SEP-IRA | Up to 25% of net self-employment income | Simple admin, high and variable profit |
| Solo 401(k) | Employee deferral plus an employer share | Maximising contributions at moderate profit |
| SIMPLE IRA | Lower limits, mandatory employee match | Very small businesses with staff |
| Traditional / Roth IRA | Smaller annual limit, stackable | Everyone, alongside the plans above |
A solo 401(k) usually beats a SEP-IRA below roughly $150,000 of profit because the employee deferral is not percentage-limited. Model the long-run effect with the retirement calculator.
When an S-Corporation Election Starts to Pay
As a sole proprietor, all profit is subject to self-employment tax. Electing S-corporation status lets you split profit between a reasonable W-2 salary (subject to payroll tax) and distributions (not subject to it).
- Below roughly $80,000 of profit the savings rarely cover payroll processing, a separate return and state fees.
- At $150,000 of profit with a $75,000 reasonable salary, the payroll-tax saving can exceed $10,000 per year.
- 'Reasonable compensation' is enforced by the IRS — an artificially low salary is a frequent audit trigger.
- Some states (notably California) impose additional franchise taxes and fees on S-corporations.
- You keep filing quarterly, now as payroll deposits plus personal estimates.
Compliance Calendar and Common Mistakes
- Quarterly estimated tax due around 15 April, 15 June, 15 September and 15 January.
- Pay the lesser of 90% of this year's liability or 100% of last year's (110% if prior-year AGI exceeded $150,000) to be inside the safe harbour.
- File Schedule C and Schedule SE with Form 1040; add Form 8995 for QBI and Form 2210 if you use the annualized method.
- Keep business and personal banking separate and reconcile monthly.
- Do not forget state and, in some cities, local business taxes and registrations.
- Track mileage and home-office square footage during the year — reconstructing them in April rarely survives scrutiny.
Size your instalments with the quarterly tax calculator and estimate the cost of a missed payment with the estimated tax penalty calculator.