The short version
If you expect to owe $1,000 or more after withholding, the IRS expects tax during the year, not only in April. Add self-employment tax (15.3% of 92.35% of your profit, up to the Social Security cap) to income tax on the rest, and pay at least the smaller of 90% of this year's total or 100% of last year's, in four installments. For a single freelancer with $80,000 of profit and nothing else, that is a federal total of $18,830 and four payments of $4,237, or four of $2,250 if last year's tax was $9,000.
2026 estimated tax calculator
Federal tax for 2026 only. Married filing separately has different brackets at higher incomes and a $125,000 extra Medicare threshold, so this calculator does not cover it. Nothing you enter leaves this page.
How the calculator works
Six steps, in this order. The tables and brackets come straight from the IRS, listed under Sources.
| Step | What it does | How |
|---|---|---|
| 1 | Self-employment tax | Net profit x 92.35%, then 12.4% Social Security up to the wage base, plus 2.9% Medicare on all of it. Extra 0.9% Medicare above $200,000 ($250,000 joint). |
| 2 | Half of SE tax is deducted | Half of the 15.3% parts reduces your adjusted gross income. It does not reduce the SE tax itself. |
| 3 | Taxable income | Wages + other income + profit - half of SE tax - the standard deduction ($16,100 single, $32,200 joint, $24,150 head of household) - your other deductions. |
| 4 | Income tax | The 2026 brackets applied to taxable income, less credits. |
| 5 | Total tax | Income tax + SE tax. This is the number the safe harbor is a share of. |
| 6 | What to pay | The smaller of 90% of this year's total and the prior-year amount (100% or 110%), less withholding and payments made, divided by the dates left. |
The Social Security part stops at the 2026 wage base of $184,500. If you also have W-2 wages, those wages use up the base first, which is why the calculator asks for them. The tax on wages is withheld by your employer, so you enter the amount withheld and it counts as already paid.
Three worked examples
All three come from the same code as the calculator. Round numbers, federal only, standard deduction, no credits.
| Case | Inputs | SE tax | Income tax | Total federal tax | Per $1 of profit |
|---|---|---|---|---|---|
| Self-employed, single | $80,000 profit, nothing else | $11,304 | $7,527 | $18,830 | 24 cents |
| Day job plus side work, single | $60,000 wages, $6,000 withheld, $30,000 profit | $4,239 | $10,504 | $14,743 | n/a |
| High earner, single | $300,000 profit | $31,606 | $62,725 | $94,330 | 31 cents |
The first case, line by line. Profit of $80,000 gives net earnings of $73,880 (92.35%). Social Security is 12.4% of that, $9,161, and Medicare 2.9%, $2,143, for SE tax of $11,304. Half, $5,652, comes off income, leaving an adjusted gross income of $74,348. Subtract the $16,100 standard deduction for taxable income of $58,248. The bands are 10% on the first $12,400, 12% up to $50,400 and 22% above it, which is $7,527. Add SE tax and the total is $18,830.
The third case shows the cap. At $300,000 of profit, net earnings are $277,050, but Social Security stops at $184,500, so it is 12.4% of $184,500 and not of the whole amount. The extra 0.9% Medicare tax applies to the $77,050 above $200,000, $693. SE tax is $31,606 against $42,389 if the cap did not exist.
What to pay, and the safe harbor
You generally avoid the penalty if you owe under $1,000 after subtracting withholding and refundable credits. Otherwise, the IRS says you must have paid at least 90% of this year's tax or 100% of last year's, whichever is smaller. The 110% version for higher earners is in Form 1040-ES: if last year's adjusted gross income was over $150,000 ($75,000 married filing separately), you need 110% of last year's tax for the prior-year test.
Why it matters: in the first example, 90% of this year's tax is $16,947, so the current-year test asks for $4,237 per installment. If last year's total tax was $9,000, the prior-year test needs only $9,000, so $2,250 per installment, and the rest is a balance you pay with your return. The catch is a second bill in April. If your income jumped, the prior-year option leaves you owing the difference, and the calculator shows both numbers so you can decide.
The 2026 due dates
For a calendar-year taxpayer, the four installments are below. If a date falls on a weekend or legal holiday, the deadline moves to the next business day. None of the four falls on a weekend this year.
| # | Due date | Day of the week | Example payment |
|---|---|---|---|
| 1 | April 15, 2026 | Wednesday | $4,237 at the current-year test |
| 2 | June 15, 2026 | Monday | $4,237 at the current-year test |
| 3 | September 15, 2026 | Tuesday | $4,237 at the current-year test |
| 4 | January 15, 2027 | Friday | $4,237 at the current-year test |
The January 15, 2027 payment is not required if you file your 2026 return by February 1, 2027 and pay the whole balance with it (January 31 falls on a Sunday). Check the current Form 1040-ES instructions before you rely on that. Income earned unevenly can use the annualized income method on Form 2210, which allows smaller early payments.
How to pay
The IRS lists these options: mail a check with a Form 1040-ES voucher, pay online or by phone, pay through the IRS app, or pay through your IRS online account. Keep the confirmation number with your records, because it is how you prove the payment date.
Turning it into a rule for your invoices
Federal tax is the number that surprises people, because no one withholds it. The cents-per-dollar line gives you a rule: with $80,000 of profit and nothing else, set aside about 24 cents of each dollar of profit, plus your state. When an invoice is paid, move that share to a separate account, and the four payments stop being a scramble. Profit is revenue minus expenses, so the profit margin calculator and the mileage calculator both feed this one. If you are not sure what to charge in the first place, start with the freelance rate calculator, which works backward from the income you want.
What this does not cover
- State and local tax. Add your state's estimate on top.
- The qualified business income deduction. It has income limits and its own form. Enter it in the other deductions box if you expect it.
- Capital gains, the child tax credit phase-outs and other taxes. Put credits in the credits box and other income in the income box as ordinary income.
- Itemizing. If your itemized deductions exceed the standard deduction, enter the excess in other deductions.
- Next year. These are 2026 figures. The IRS publishes 2027 amounts in a revenue procedure around the end of the year.
It is an estimate. A tax professional who can see your whole return will beat any web calculator, and the IRS Tax Withholding Estimator is the better tool if you are mostly an employee.
Sources
- IRS Revenue Procedure 2025-32, 2026 brackets and standard deduction, read 5 November 2026
- IRS Topic 554, self-employment tax ($400, 92.35%, 12.4% + 2.9%, deduction of half, extra Medicare thresholds)
- IRS, estimated taxes ($1,000 test, 90% and 100% safe harbors, how to pay, Form 2210)
- IRS Topic 306, underpayment penalty
- IRS Form 1040-ES (2026), due dates and the 110% rule; the 110% rule and dates were confirmed through reports citing this form, and we could not open the PDF text, so check the form
- Social Security Administration notice of the 2026 contribution and benefit base, Federal Register, 3 November 2025 ($184,500)
- American Payroll Association, 2026 Social Security wage base $184,500, reporting the Social Security Administration's 24 October 2025 announcement; the SSA page itself returned an access error when we tried it
Common questions
Who has to pay estimated tax?
Individuals, including sole proprietors, partners and S corporation shareholders, generally must pay estimated tax if they expect to owe $1,000 or more when they file, according to the IRS. If you have a job with withholding, the withholding counts toward that $1,000 test.
What are the 2026 estimated tax due dates?
April 15, June 15 and September 15, 2026, and January 15, 2027, for a calendar-year taxpayer. When a date falls on a weekend or legal holiday, the deadline moves to the next business day. The January 2027 payment is not required if you file your 2026 return by February 1, 2027 and pay the whole balance with it (January 31 falls on a Sunday), so check the current Form 1040-ES text.
What is the safe harbor for estimated tax?
You generally avoid the underpayment penalty if you owe less than $1,000 after withholding, or if you pay at least the smaller of 90% of this year's tax or 100% of last year's tax. If last year's adjusted gross income was over $150,000 ($75,000 if married filing separately), the prior-year test is 110%, not 100%.
Do I owe self-employment tax if I earned less than $400?
The IRS says you generally owe it when your net earnings from self-employment are $400 or more. Net earnings are 92.35% of your net profit, so the practical line is a little above $433 of profit. The calculator applies that test.
Does this include state income tax?
No. It is a federal calculator. Most states with an income tax have their own estimated payments and due dates, and some use different dates. Add your state's tax on top, or use your state revenue agency's calculator.
How much of each invoice should I set aside?
With no other income, a federal total of about 24 cents per dollar of profit at $80,000, as the example below shows. It rises with income and falls with deductions, and it excludes state tax. Enter your own figures and use the cents-per-dollar line the calculator prints.
What if I miss a payment or pay too little?
The IRS can charge an underpayment penalty, calculated on Form 2210. If your income is uneven, annualizing it and making unequal payments may reduce or avoid the penalty. The penalty may also be waived in some cases such as a casualty or disaster.
Does the calculator include the 20% qualified business income deduction?
No. That deduction has income limits and a separate calculation on Form 8995, so we leave it out rather than guess. If you expect to claim it, enter the amount in the other deductions box.
What this is. A calculator and guide written by InvoiceTools. It is an estimate for planning, not tax advice or a return. Figures are the IRS and SSA amounts for 2026 read on 5 November 2026.
Last reviewed by InvoiceTools, Houston, Texas, on 5 November 2026.