Updated November 1, 2026 for the 2026 tax year
Why the percentage is higher than you expect
A W-2 employee's taxes come out of each paycheck. When you're self-employed, nothing is taken out, and your profit carries three taxes: self-employment tax (about 14% of profit after the 92.35% adjustment), federal income tax at your bracket, and state income tax. Together that's often 25% to 35% of profit for a typical small business owner.
A simple system that works
- Open a separate savings account just for taxes.
- Every time a payment comes in, move the percentage from this calculator into it.
- Pay your quarterly estimates from that account on the IRS due dates.
If there's money left over in April, it's a bonus. If you come up short, raise the percentage next year.
What this calculator includes
- Self-employment tax at 15.3% on 92.35% of profit, with the 2026 Social Security wage base of $184,500.
- Federal income tax using 2026 brackets, the standard deduction and the 20% QBI deduction.
- Only the extra tax caused by the business, so W-2 wages and their withholding are counted separately.
- State tax as a flat rate you enter. Missouri's top rate is 4.7%.
For the exact payments and due dates, use the quarterly tax estimator.
Common questions
What percent should a self-employed person set aside for taxes?
Commonly 25% to 35% of profit, but it depends on your total income, filing status and state. Enter your numbers above for a specific figure.
Is the percentage based on revenue or profit?
Profit: what's left after business expenses. If you save from revenue instead, use a lower percentage, roughly your rate times your profit margin.
Does Missouri have a state income tax?
Yes. Missouri's top individual rate is 4.7%, and it applies to most taxable income above a low threshold.
Sources: IRS Rev. Proc. 2025-32 (2026 brackets and standard deduction), Social Security Administration 2026 wage base, Tax Foundation, Missouri individual income tax.