If you earn money outside a W-2 job — freelancing, consulting, gig work, a side business — no employer withholds taxes for you. The IRS still expects its share four times a year through quarterly estimated tax payments. Miss them and you can face an underpayment penalty on top of the tax bill itself. This free estimated tax calculator estimates what a freelancer or sole proprietor owes for 2026, broken into self-employment tax, federal income tax, and a per-quarter payment.
The math has two parts. First, self-employment tax: 15.3% on 92.35% of your net profit — 12.4% for Social Security on the first $184,500 of earnings (the official 2026 wage base) and 2.9% for Medicare on every dollar. Second, ordinary federal income tax on what remains, after deducting half of your self-employment tax and the 2026 standard deduction ($16,100 single, $32,200 married filing jointly). The calculator runs both halves with the official 2026 brackets, then divides your total into four equal quarterly payments.
You can also enter W-2 wages from a day job. Wages count toward the $184,500 Social Security cap first, which can lower the Social Security portion of your self-employment tax — the calculator coordinates this automatically. And if you know last year's total tax, it checks your estimate against the IRS safe harbor: pay 100% of last year's tax and you generally avoid the underpayment penalty even if this year's estimate runs a little low.
How to use the Estimated Tax Calculator
- Enter your expected 2026 freelance or business revenue and your deductible business expenses — the calculator works with the difference (net profit).
- Add W-2 wages from a day job if you have one (optional). This coordinates the Social Security cap and can lower your result.
- Choose your filing status — single or married filing jointly — to get the right brackets and standard deduction.
- Optionally enter last year's total tax to see your IRS safe-harbor quarterly target.
- Click Calculate quarterly tax. Your payment per quarter appears with a full breakdown. The 2026 due dates are April 15, June 15 and September 15, 2026, plus January 15, 2027.
Tips for accurate results
- Set aside 25–30% of every freelance payment in a separate account, so quarterly deadlines never hurt.
- If your income is lumpy, the IRS lets you annualize each quarter instead of paying equal fourths — worth discussing with a tax pro.
- The half-SE-tax deduction only lowers income tax, not SE tax itself — the calculator already handles this.
- State taxes are extra: most states want their own quarterly estimates, with separate forms and deadlines.
2026 figures this calculator uses
All numbers are the official 2026 federal figures: a $184,500 Social Security wage base (12.4% up to the cap, 2.9% Medicare uncapped, plus 0.9% additional Medicare over $200,000 single / $250,000 joint), the 92.35% self-employment earnings factor, standard deductions of $16,100 (single) and $32,200 (married filing jointly), and the seven 2026 marginal brackets (10% through 37%). It is an estimate for planning — not tax advice.
Frequently asked questions
Who has to pay quarterly estimated tax?
Generally, anyone who expects to owe $1,000 or more at filing after withholding and credits. For freelancers, the trigger is usually $400 or more in net earnings, which creates a self-employment tax obligation.
What is the IRS safe harbor rule?
Pay at least 90% of this year's tax — or 100% of last year's tax (110% if prior-year AGI exceeded $150,000) — through withholding and timely quarterly payments, and you generally avoid the underpayment penalty even if your estimate was a little low.
When are the 2026 estimated payments due?
April 15, June 15 and September 15, 2026, and January 15, 2027, using Form 1040-ES, IRS Direct Pay, or mail.
I also have a W-2 job. Do I still owe estimated tax on freelance income?
Yes — W-2 withholding doesn't cover freelance profit. Your wages do count toward the Social Security wage base first, which can reduce the Social Security part of your self-employment tax; this calculator coordinates that for you.
Is this tax advice?
No. It is a planning estimate based on 2026 federal figures. Deductions, credits, state taxes and special situations are not included — consult a qualified tax professional before filing or paying.