How to use this self-employment tax calculator
Select your country from the dropdown, then enter your total gross annual income from self-employment (before any deductions) and your total business expenses for the year. The calculator estimates your self-employment tax (Social Security + Medicare in the US, National Insurance in the UK, CPP in Canada), federal income tax, effective tax rate, and take-home pay.
For the most accurate estimate, include all deductible business expenses: home office costs, equipment and supplies, software subscriptions, professional services, travel, marketing, insurance, and retirement contributions. The larger your legitimate deductions, the lower your taxable base.
Understanding US self-employment tax
If you're a freelancer, independent contractor, gig worker, or sole proprietor in the United States, you owe self-employment tax on net earnings above $400. The SE tax rate is 15.3%, split between Social Security (12.4%) and Medicare (2.9%). This applies to 92.35% of your net profit — the IRS gives you this reduction to mirror the fact that employers don't pay FICA on their own FICA contribution.
The Social Security portion has a wage cap: for 2024, you only pay the 12.4% on the first $168,600 of earnings. The Medicare portion has no cap, and if your earnings exceed $200,000 (single) or $250,000 (married filing jointly), you pay an additional 0.9% Medicare surtax on the excess.
The good news: you can deduct half of your SE tax when calculating adjusted gross income. This doesn't reduce your SE tax itself, but it lowers your income tax. This calculator accounts for that deduction.
Self-employment tax in other countries
United Kingdom: Self-employed individuals pay Class 2 National Insurance (£3.45/week if profits exceed £12,570) and Class 4 NI (6% on profits between £12,570 and £50,270, 2% above that). These fund the state pension and NHS.
Canada: Self-employed workers pay both the employee and employer portions of Canada Pension Plan (CPP) contributions — 11.9% on earnings between $3,500 and $68,500. Half of CPP is deductible against income.
Australia: There's no separate self-employment tax. Sole traders pay income tax through the regular bracket system plus a 2% Medicare levy. The tax-free threshold is A$18,200. Superannuation (retirement) contributions are voluntary for the self-employed.
For countries not individually modeled, the calculator uses a simplified 15% social contribution + 20% income tax estimate. Always consult a local tax professional for precise obligations in your jurisdiction.
Strategies to reduce your self-employment tax
Maximize deductions: Track every legitimate business expense. Use accounting software or spreadsheets to categorize expenses throughout the year rather than scrambling at tax time. Common overlooked deductions: mileage, professional memberships, continuing education, and a portion of your phone/internet bills.
Contribute to retirement: In the US, SEP-IRA contributions (up to 25% of net SE earnings, max $69,000 in 2024) reduce taxable income. Solo 401(k) plans allow even higher contributions. In the UK, pension contributions reduce taxable profits. In Canada, RRSP contributions provide a deduction.
Consider your business structure: In the US, forming an S-Corp lets you pay yourself a reasonable salary (subject to FICA) and take remaining profits as distributions (not subject to SE tax). This only makes sense above a certain income level — typically $60,000+ in net profit. Consult a CPA before restructuring.
Health insurance deduction: Self-employed individuals in the US can deduct 100% of health insurance premiums for themselves, their spouse, and dependents. This reduces adjusted gross income and, indirectly, income tax — though it doesn't reduce SE tax directly.
Frequently Asked Questions
What is self-employment tax?
In the US, self-employment tax is the Social Security and Medicare tax that self-employed individuals pay. Employees split these taxes with their employer (7.65% each), but self-employed people pay both halves — 15.3% total (12.4% Social Security + 2.9% Medicare) on 92.35% of net earnings. Other countries have equivalent social contribution systems.
Can I deduct business expenses before calculating SE tax?
Yes. You calculate self-employment tax on net profit (gross income minus legitimate business expenses). Common deductions include home office costs, equipment, software, internet, travel, professional development, health insurance premiums, and retirement contributions. The more deductions you claim, the lower your SE tax base.
What is the 92.35% factor in US self-employment tax?
The IRS allows you to multiply your net earnings by 92.35% (100% minus half of 15.3%) before applying the SE tax rate. This mirrors the fact that employers don't pay FICA on the employer's share of FICA — it effectively gives self-employed individuals the same treatment as employees whose employer-paid FICA isn't counted as taxable wages.
Do I need to make quarterly estimated payments?
In most countries, yes. In the US, if you expect to owe $1,000 or more in tax, you must pay quarterly estimates (April 15, June 15, September 15, January 15). Failure to pay on time results in underpayment penalties. Other countries have similar installment requirements for self-employed individuals.
Does this calculator include state or provincial tax?
No. This calculator estimates federal/national-level self-employment and income taxes. State, provincial, or local taxes vary widely and are not included. Add your local tax rate on top of these estimates for a complete picture.
Privacy and methodology
This calculator runs entirely in your browser — no income data is sent to any server. Tax calculations use published 2024 rates for supported countries. Results are estimates for planning purposes. Actual tax liability depends on filing status, additional deductions, credits, state/provincial taxes, and other factors not modeled here. This tool does not constitute tax advice — consult a qualified tax professional for your specific situation.