Quick answer
On $85,000 of net freelance income in 2026, total tax comes to about $20,968 — $5,242 per quarter — at a 4.5% state rate with the QBI deduction claimed. Self-employment tax alone is $12,010, more than half the bill, because no employer withholds anything from 1099 income.
How the Quarterly Estimated Tax Calculator works, step by step
Enter your net business income — revenue minus Schedule C expenses — your state income tax rate, and whether you claim the QBI deduction. The calculator models a single filer for tax year 2026, using the $16,100 standard deduction and the 2026 federal brackets. It estimates federal income tax, self-employment tax and state tax, then divides the total into four equal quarterly payments.
Self-employment tax comes first. Your net income is multiplied by 92.35% to find net earnings from self-employment, then taxed at 15.3%: 12.4% for Social Security on earnings up to the $184,500 wage base for 2026, plus 2.9% for Medicare on all earnings. Half of the resulting tax is deductible from your income, which softens the blow on the income-tax side.
Federal income tax is calculated on what is left. Adjusted gross income is net income minus half the self-employment tax; then the $16,100 standard deduction and the 20% QBI deduction come off. The QBI deduction is permanent from 2026 under the One Big Beautiful Bill Act, and the full 20% applies below $201,750 of taxable income for single filers. The 2026 brackets then apply: 10% to $12,400, 12% to $50,400 and 22% to $105,700.
State tax is estimated as your adjusted gross income multiplied by the state rate you enter — 4.5% by default. Add the three taxes together and divide by four for the quarterly payment, due April 15, June 15 and September 15, 2026, with the final installment on January 15, 2027. The calculator also shows your effective tax rate: total tax divided by net income.
The safe harbor rule decides whether a short payment draws a penalty. Pay at least the smaller of 90% of this year's tax or 100% of last year's tax in four on-time installments, and no underpayment penalty applies; the prior-year figure rises to 110% if last year's adjusted gross income exceeded $150,000. You must make estimated payments if you expect to owe $1,000 or more after withholding and credits.
The formula
Quarterly payment = (self-employment tax + federal income tax + state tax) ÷ 4, where self-employment tax = net income × 92.35% × 15.3%, with the 12.4% Social Security portion capped at the $184,500 wage base.
Worked example — try it on the calculator above
Worked example: $85,000 net income, single filer, 2026
Net income is $85,000 and the state rate is 4.5%, with the QBI deduction claimed. Self-employment earnings are $85,000 × 92.35% = $78,497.50; Social Security tax is $9,733.69 and Medicare is $2,276.43, for $12,010.12 of self-employment tax. Adjusted gross income is $78,994.94, the QBI deduction is $15,798.99, and taxable income after the $16,100 standard deduction is $47,095.95. Federal income tax is $5,403.51 and state tax is $3,554.77, so the total is $20,968.40 — a quarterly payment of $5,242.10 and an effective rate of 24.7%. The Social Security portion stays below the $184,500 wage base, so the cap does not bind at this income; it starts to matter above roughly $200,000 of net income.
Frequently Asked Questions
How do you calculate 1099 quarterly estimated taxes?
Multiply net freelance income by 92.35% and apply the 15.3% self-employment tax. Subtract half that tax and the $16,100 standard deduction, apply the 20% QBI deduction if eligible, then run the result through the federal brackets and add state tax. Divide the total annual liability by four for each quarterly payment.
What is the self-employment tax rate for freelancers in 2026?
The rate is 15.3%: 12.4% for Social Security on net earnings up to the $184,500 wage base, plus 2.9% for Medicare on all net earnings. It applies to 92.35% of net profit, not the full amount. Above $200,000 of earnings ($250,000 married filing jointly), an additional 0.9% Medicare tax applies.
What are the IRS safe harbor rules for quarterly payments?
Pay the smaller of 90% of this year's total tax or 100% of last year's total tax, in four on-time installments, and the underpayment penalty does not apply. If last year's adjusted gross income exceeded $150,000 ($75,000 married filing separately), the prior-year figure becomes 110%. The penalty is avoided even if you still owe a balance at filing.
What happens if I miss a quarterly estimated tax payment?
Pay it as soon as possible — the underpayment penalty works like interest and accrues daily until the shortfall is paid. The IRS rate was 7% for most of 2026 (6% for April through June). The penalty is calculated on Form 2210 and can apply even if you pay in full with your return, because the installments themselves were late.
Estimates, not advice. This calculator provides educational estimates based on the inputs you enter and the assumptions shown on this page. It is not financial, tax or investment advice, and it cannot see your full situation. Verify important figures against official sources, and consider a qualified professional for decisions about your own money. See our Disclaimer and Methodology.