Quarterly estimated tax calculator for the self-employed

Put in what you expect the business to make this year, and see what to send the IRS each quarter: self-employment tax, income tax and the amount that avoids an underpayment penalty, worked out the way the IRS's 2026 Form 1040-ES does it.

4 paymentsApril, June, September, January

1040-ESThe IRS's own 2026 worksheet

FreeNo email, no sign-up

Pay each quarter

$4,236.81

Four payments, April 15, 2026 to January 15, 2027

$18,830Total 2026 tax

$11,304Self-employment tax

23.5%Share of your profit

An estimate from the 1040-ES worksheet. It leaves out capital gains, the alternative minimum tax and state income tax. If your income is uneven, the annualized method in IRS Publication 505 can lower early payments.

How we got this

Self-employment earnings$80,000.00 × 92.35% = $73,880.001040-ES (2026) self-employment tax worksheet, line 3.
Medicare part$73,880.00 × 2.9% = $2,142.52
Social Security part$73,880.00 × 12.4% = $9,161.12Only earnings up to $184,500 for 2026, less any W-2 wages, are taxed for Social Security.
Self-employment tax$11,303.64, and half of it, $5,651.82, comes off your income
Adjusted gross income$80,000.00 − $5,651.82 = $74,348.18
Taxable income$74,348.18 − $16,100.00 standard deduction = $58,248.18
Income tax$5,800.00 + ($58,248.18 − $50,400.00) × 22% = $7,526.602026 Tax Rate Schedules from the 1040-ES.
Total 2026 tax$7,526.60 income tax + $11,303.64 self-employment tax = $18,830.24
Required for the year90% × $18,830.24 = $16,947.22
Each quarter($16,947.22 − $0.00 withheld) ÷ 4 = $4,236.81

Payment	Due	Amount
1	April 15, 2026	$4,236.81
2	June 15, 2026	$4,236.81
3	September 15, 2026	$4,236.81
4	January 15, 2027	$4,236.81
Total		$16,947.24

Sources: IRS Form 1040-ES (2026), Estimated Tax for Individuals; IRS, Estimated taxes; IRS Topic 560, Additional Medicare Tax; IRS, Self-employment tax (Social Security and Medicare taxes). Checked 2026-10-09.

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Key takeaways

Self-employment tax is 15.3% of 92.35% of your net profit: 12.4% Social Security on earnings up to $184,500 for 2026 and 2.9% Medicare on all of it.
You generally need to pay estimated tax if you expect to owe at least $1,000 after withholding and credits.
To avoid the penalty, pay the smaller of 90% of this year's tax or 100% of last year's (110% if last year's AGI was over $150,000).

Who has to pay estimated tax

When you work for yourself, nobody withholds tax from your pay, so the IRS expects you to pay as you go. The 2026 Form 1040-ES says you generally must pay estimated tax if both of these are true:

You expect to owe at least $1,000 in tax for 2026 after withholding and refundable credits.
You expect your withholding and refundable credits to be less than the smaller of 90% of your 2026 tax or 100% of the tax on your 2025 return, which must cover all 12 months.

If your 2025 adjusted gross income was more than $150,000 ($75,000 married filing separately), the prior-year figure is 110% instead of 100%.

2026 due dates

Payment	Due
1	April 15, 2026
2	June 15, 2026
3	September 15, 2026
4	January 15, 2027

The 1040-ES says you do not have to make the January 15, 2027 payment if you file your 2026 return by February 1, 2027 and pay the whole balance with it. A payment mailed and postmarked by the due date counts as paid on time.

How self-employment tax works

Self-employment tax is the Social Security and Medicare an employer and employee would split, paid by you alone. From the 1040-ES worksheet:

Multiply your net profit by 92.35%.
Medicare: multiply that by 2.9%.
Social Security: multiply the smaller of that amount or $184,500 less any W-2 wages by 12.4%.
Add them. Half of the total is a deduction when you work out your adjusted gross income.

Example: $80,000 of profit. $80,000 × 92.35% = $73,880. Medicare is $2,142.52 and Social Security $9,161.12, so self-employment tax is $11,303.64, and $5,651.82 of it comes off your income.

Income tax, and a worked example

Income tax is worked out on taxable income: your adjusted gross income less the standard deduction (for 2026, $16,100 single, $32,200 married filing jointly, $24,150 head of household) or your itemized deductions, and less any qualified business income deduction. The calculator then uses the 2026 Tax Rate Schedules from the 1040-ES.

Continuing the example, single: $80,000 − $5,651.82 = $74,348.18 of adjusted gross income. Less the $16,100 standard deduction leaves $58,248.18 taxable. Schedule X gives $5,800 + 22% of the amount over $50,400 = $7,526.60. Total tax is $7,526.60 + $11,303.64 = $18,830.24. Ninety percent is $16,947.22, or about $4,236.81 a quarter.

Set it aside as you goThe simplest habit: move a share of every customer payment into a separate tax account the day it lands, then pay the quarter from there. The calculator shows your total tax as a share of profit, which is a good starting share.

What this estimate leaves out

State income tax, which your state may also collect through its own estimated payments.
Capital gains, the alternative minimum tax and other special taxes.
The exact qualified business income deduction, which depends on your income and business; type it in if your preparer gives you a number.
Uneven income: the annualized installment method in IRS Publication 505 can lower early payments if most of your money comes late in the year.

Keep good books and this gets easy. Koira's QuickBooks Online integration on the Grow plan keeps invoices and payments in your books, and our W-9 and 1099-NEC guide covers paying subs.

Last checked October 9, 2026.

FAQ

How much should I set aside for taxes when self-employed?

Run your numbers in the calculator: it shows your total tax as a share of profit. Self-employment tax alone is about 15.3% of 92.35% of profit, before any income tax.

When are quarterly estimated taxes due for 2026?

April 15, 2026, June 15, 2026, September 15, 2026 and January 15, 2027, according to the 2026 Form 1040-ES.

What happens if I do not pay estimated taxes?

You may owe a penalty for underpaying, even if you are due a refund when you file. Paying at least the smaller of 90% of this year's tax or 100% of last year's (110% for higher incomes) generally avoids it.

Do I have to pay estimated tax in my first year?

The 1040-ES has an exception: you do not have to pay estimated tax for 2026 if you had no tax liability for the full 12 months of 2025 and were a US citizen or resident all year.

Can I pay all of my estimated tax at once?

Yes. The 1040-ES says you can pay all of your estimated tax by April 15, 2026, or in four equal amounts by the due dates.

Does a W-2 job change my estimated tax?

Yes. Wages count toward the Social Security wage base, which can lower the Social Security part of self-employment tax, and the income tax withheld from your wages counts toward what you owe. You can also raise your W-4 withholding instead of making estimated payments.

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