Self-Employed Tax Estimate Calculator: 2026 Full Guide
Self-employed workers face three tax stacks: federal income tax, 15.3% self-employment tax, and state income tax. Our free [self-employed tax estimate calculator](https://gigmytax.com/calculators/self-employed-tax-estimator) rolls all three into one 2026 estimate — so you know exactly what to send the IRS.
How the self-employed tax estimate calculator works
Inputs: 1099 income, mileage, expenses, health insurance, retirement contributions, filing status, and state. Outputs: net SE income, SE tax, federal tax, state tax, quarterly payment, and refund/owed.
The three-tax stack every self-employed person owes
**1) Federal income tax** — 10–37% marginal brackets. **2) SE tax** — 15.3% on net profit up to $176,100 (2026 SS wage base), 2.9% Medicare uncapped. **3) State tax** — 0–13.3% depending on state.
2026 numbers built into the calculator
Standard deduction $15,000 (single) / $30,000 (MFJ). SS wage base $176,100. Mileage rate $0.70/mi. QBI 20% pass-through deduction still active. 199A phase-outs at $241,950 (single) / $483,900 (MFJ).
Above-the-line deductions the calculator handles
Half of SE tax, self-employed health insurance (100% of premiums), SEP-IRA / Solo 401(k) / SIMPLE IRA contributions, and HSA. These reduce AGI *before* the standard deduction — the highest-value cuts you get.
Below-the-line deductions on Schedule C
Mileage OR actual vehicle expenses, home office (simplified $5/sqft up to 300 sqft), phone %, internet %, software, supplies, professional services, education, advertising, and travel.
QBI deduction — the 20% you don't want to miss
Section 199A gives most self-employed workers an extra 20% deduction on qualified business income. Below the phase-out, it's automatic. A $60,000 net gets a $12,000 QBI deduction on top of everything else.
When you owe quarterly estimated tax
If you'll owe $1,000+ at year end, pay Form 1040-ES on Apr 15, Jun 16, Sep 15, Jan 15. Safe harbor: pay 100% of last year's tax (110% if AGI > $150K) and skip the underpayment penalty.
Worked example — freelance designer in Illinois
$85,000 gross, 3,000 mi ($2,100), $6,000 expenses, $6,000 SEP-IRA, $4,800 health premiums = ~$66,100 net SE. SE tax ≈ $9,350, federal ≈ $6,100, IL 4.95% ≈ $2,750 → total ≈ **$18,200**. Save ~21% of gross.
Common mistakes the estimator prevents
Skipping the ½ SE deduction, missing QBI, forgetting the standard deduction, ignoring self-employed health insurance, and using outdated 2024 mileage rates ($0.67 instead of $0.70).
Related calculators
[Quarterly tax calculator](https://gigmytax.com/calculators/quarterly-tax), [SE tax calculator](https://gigmytax.com/calculators/self-employment), [tax deduction stacker](https://gigmytax.com/calculators/tax-deduction), and state-specific: [California](https://gigmytax.com/calculators/california-self-employed-tax), [Texas](https://gigmytax.com/calculators/texas-self-employed-tax), [New York](https://gigmytax.com/calculators/new-york-self-employed-tax).
Frequently asked questions
+How accurate is a self-employed tax estimate calculator?
Within ~5% of your actual 1040 result if you enter true 1099 totals, complete deductions, and correct filing status. It uses IRS 2026 brackets and current SE/QBI rules.
+Do I need to pay quarterly if I have a W-2 job too?
Only if W-2 withholding won't cover your total tax. Either pay 1040-ES or increase your W-4 withholding to absorb the side income.
+What's the difference between SE tax and income tax?
SE tax is Social Security + Medicare (15.3%). Income tax is the federal bracket tax. Self-employed workers owe both on the same net profit.
+Does the calculator include the QBI deduction?
Yes — the estimator applies the 20% Section 199A deduction automatically for taxpayers under the phase-out thresholds.
+Can I deduct my health insurance premiums?
Yes — 100% as an above-the-line deduction (reducing AGI) if you're not eligible for a subsidized employer plan through a spouse.
Related calculators
- Self-Employed Tax EstimatorEstimate federal, SE, and state tax for your full 1099 year.
- Side Hustle Tax CalculatorEstimate tax on side-gig 1099 income stacked on your W-2.
- Freelancer Quarterly Tax CalculatorForm 1040-ES quarterly payments for freelance 1099 income.
- Self-Employment Tax CalculatorCalculate the 15.3% SECA tax on your net 1099 income.
Related guides
- Self-Employed Tax Estimator: The 2026 Federal, SE & State GuideHow to accurately estimate 2026 self-employed taxes — federal income tax, 15.3% SE tax, and state tax — with real formulas and a free calculator.
- Self-Employment Tax Explained: 2026 Rates, Rules, and MathSelf-employment tax explained in plain English: 15.3% breakdown, the 92.35% adjustment, the ½ SE deduction, thresholds, and how to pay it in 2026.
- How Much Should I Save for Taxes as a Self-Employed Worker in 2026The exact % of every 1099 payout to save for taxes in 2026. Covers federal, self-employment, and state tax for freelancers, gig workers, and contractors.
- Quarterly Tax Deadlines Explained: The 2026 Form 1040-ES CalendarThe 2026 IRS quarterly tax deadlines for 1099 workers: April 15, June 15, September 15, and January 15, 2027. Safe-harbor rules, penalties, and how to pay.
- 1099 Tax Guide for Beginners: The 2026 WalkthroughNew to 1099 income? This beginner's guide covers forms, quarterly taxes, deductions, SE tax, and how to file — everything you need for the 2026 tax year.