Blog · 30 October 2026 · Tax year 2026

How much should I pay in quarterly taxes?

If you are self-employed, the IRS does not wait until April for its money. US tax is pay-as-you-go: if you expect to owe at least $1,000 in federal tax for the year after withholding and credits, you generally have to pay in four instalments during the year. This post gives you the exact formula, then works it through twice, so you can see what your own number should look like before you run the quarterly estimated tax calculator.

The short answer

Your quarterly payment is (expected total federal tax − federal withholding) ÷ 4. “Total federal tax” here means two taxes added together: self-employment tax plus federal income tax. A common rule of thumb — set aside 25–30% of net profit — is a decent savings habit, but it is not your payment: as the examples below show, a single filer on $60,000 of profit owes about 20% of profit, and on $100,000 about 22%. The only exact answer comes from running your own figures.

Step by step, tax year 2026

1. Start with net profit — business income minus deductible business expenses (the Schedule C figure). Not gross billings.
2. Self-employment tax: net earnings are 92.35% of net profit, taxed at 15.3% (12.4% Social Security up to the 2026 wage base of $184,500, plus 2.9% Medicare). Half of the regular SE tax is deductible from income.
3. Income tax: subtract half the SE tax and the 2026 standard deduction ($16,100 single, $32,200 married filing jointly, $24,150 head of household), apply the simplified 20% QBI deduction capped at 20% of taxable income before the deduction, then apply the 2026 federal brackets (Rev. Proc. 2025-32).
4. Subtract withholding from any W-2 job, then divide what is left by four.

Full sources for every figure above are listed on the About & Sources page.

Worked example 1: $60,000 of 1099 income, single filer

Worked example 2: $100,000 of 1099 income, single filer

Notice the pattern: the SE tax alone is 14.13% of profit at these levels, and income tax adds roughly 6–8 points more. That is why the 25–30% savings rule overshoots for many single filers — it is safe for cash flow, but it is not what the IRS actually requires.

The safe-harbor shortcut

If working out this year's tax feels uncertain, the IRS safe harbor lets you pay a known number instead: pay at least the smaller of 90% of this year's tax, or 100% of last year's total tax (110% if last year's AGI was over $150,000, or $75,000 if married filing separately), spread over the four due dates, and you generally avoid the underpayment penalty even if this year's tax ends up higher. If your income fell this year, the 90%-of-this-year route is cheaper; if it rose, last year's figure protects you.

If you also have a W-2 job

Two things change. First, W-2 wages use up part of the $184,500 Social Security wage base, so the Social Security part of SE tax stops sooner. Second, W-2 withholding counts as tax paid evenly across the whole year — so raising withholding late in the year can cure an earlier shortfall in a way an extra estimated payment cannot, because estimated payments are credited only when paid. Enter both figures in the quarterly estimated tax calculator and it handles the overlap.

2026 due dates

• Quarter 1 (1 January – 31 March 2026): 15 April 2026
• Quarter 2 (1 April – 31 May 2026): 15 June 2026
• Quarter 3 (1 June – 31 August 2026): 15 September 2026
• Quarter 4 (1 September – 31 December 2026): 15 January 2027

If a date falls on a weekend or federal holiday, payment on the next business day is on time. Miss a quarter, and the penalty is worked out period by period from the shortfall and how long it stayed unpaid — there is no flat penalty figure, which is why paying at least the safe-harbor amount on time is the practical protection. If your income is very uneven through the year, the IRS annualized income installment method (Form 2210, Schedule AI) lets each payment match the income actually earned in that period.

Bottom line

Save 25–30% of each payment as a habit, but pay the number the formula gives you: (total tax − withholding) ÷ 4, or the safe-harbor amount if that is lower and you want penalty protection. Run your own figures — profit, filing status, W-2 wages and withholding, last year's tax — through the quarterly estimated tax calculator and you will have all four payments and due dates in one place.

Estimate only — not tax advice. Figures are for federal tax, tax year 2026, under the simplified assumptions on the About page (no credits, no state tax, simplified QBI). Your actual tax depends on your full return. If a figure here ever disagrees with IRS.gov, IRS.gov is right.

Sources: IRS.gov — Estimated Tax; Publication 505 (2026); Revenue Procedure 2025-32 (IR-2025-103); Self-employment tax (Social Security and Medicare taxes). Checked 30 Oct 2026.