Self-employment quarterly estimated tax calculator
Self-employment tax (Social Security + Medicare) is a fixed 15.3% rate, so this calculator applies it precisely using the 2026 Social Security wage base — then adds income tax at whatever rate you tell it, since only you know your actual bracket.
Not sure of your income tax rate? Use last year's effective or marginal rate from your return — this tool uses whichever rate you enter rather than assuming a 2026 bracket for you.
Self-employment tax (15.3%)
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Estimated income tax (federal + state)
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Total estimated tax for the year
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Suggested quarterly payment
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Last updated: September 2026 · Verified by Hugo Cardozo. Uses the IRS/SSA's official 2026 Social Security wage base ($184,500) and the statutory 15.3% self-employment tax rate.
Watch: the hidden tax freelancers get surprised by
Why self-employment tax is calculated separately from income tax
As a self-employed person, you pay both the employee and employer share of Social Security and Medicare — 15.3% combined, applied to 92.35% of your net profit (a small adjustment the IRS built in to roughly mirror how it works for employees). This is separate from, and in addition to, ordinary income tax on your profit.
The 2026 Social Security wage base
The 12.4% Social Security portion only applies up to a wage cap — $184,500 for 2026, up from $176,100 in 2025. Above that amount (combining self-employment profit and any W-2 wages), only the 2.9% Medicare portion continues to apply, uncapped. High earners above $200,000 (this threshold is fixed by law and not adjusted for inflation) also owe an Additional Medicare Tax of 0.9%.
Why this calculator asks for your own tax rate
Unlike the 15.3% self-employment rate, which is fixed by law, ordinary income tax brackets depend on your filing status, deductions, and total income — details only you or a tax preparer can pin down precisely. This tool applies whichever federal and state rate you enter to your profit (after the standard half-SE-tax deduction), rather than guessing a bracket that could easily be wrong for your specific situation.
Worked example
At $80,000 net profit with no other wages, a 15% federal rate and 5% state rate: self-employment tax comes to about $11,304, income tax (on profit reduced by the deductible half of SE tax) comes to about $14,870 combined, for a total of roughly $26,173 — about $6,543 per quarter.
Frequently asked questions
Do I actually have to pay this quarterly?
The IRS generally expects estimated tax payments in quarterly installments (mid-April, mid-June, mid-September, and mid-January of the following year) if you expect to owe $1,000 or more for the year — paying only at filing time can trigger an underpayment penalty even if you pay the full amount owed.
Why is half of my self-employment tax deductible?
The IRS lets you deduct the "employer-equivalent" half of your self-employment tax when calculating your taxable income, mirroring how an employer's share of payroll tax isn't taxed as income for a regular employee.
What if my income varies a lot throughout the year?
You can use the "annualized income" method to adjust each quarter's payment instead of dividing evenly by four — useful for seasonal or highly variable self-employment income. This calculator assumes a simple even split across four quarters.
📘 Related guide
Read the full guide: "Self-Employment Tax Explained: The 15.3% Most People Forget About".
Self-Employment Tax Explained