The short answer
If you expect to owe $1,000 or more when you file, you generally need to pay estimated tax four times a year. For 2026 the due dates are April 15, June 15 and September 15, 2026, and January 15, 2027. You avoid underpayment penalties by paying 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
The U.S. tax system is pay-as-you-go. Employees pay through withholding. If you're self-employed, own a pass-through business, or have significant investment or rental income without withholding, you're expected to pay during the year through estimated payments.
The general test: you expect to owe at least $1,000 in federal tax for the year after subtracting withholding and refundable credits.
The 2026 due dates
| Payment | Covers income earned | Due |
|---|---|---|
| Q1 | January 1 – March 31 | April 15, 2026 |
| Q2 | April 1 – May 31 | June 15, 2026 |
| Q3 | June 1 – August 31 | September 15, 2026 |
| Q4 | September 1 – December 31 | January 15, 2027 |
The quarters aren't equal lengths. Q2 covers only two months, which catches a lot of people out.
The safe harbor rules
You won't owe an underpayment penalty if your withholding plus timely estimated payments equal at least the smaller of:
- 90% of your 2026 tax, or
- 100% of your 2025 tax, or 110% if your 2025 adjusted gross income was over $150,000 ($75,000 if married filing separately)
The prior-year option is the easiest to plan around, because the number is known in advance. If your income is rising fast, it can leave a large balance due in April, so set that money aside anyway.
How to calculate your payment
- Estimate this year's net self-employment income and other income.
- Calculate self-employment tax: 15.3% on 92.35% of net earnings up to $184,500, plus 2.9% above it.
- Calculate income tax after half of the SE tax, the standard deduction ($16,100 single, $32,200 married filing jointly in 2026) and the QBI deduction.
- Compare 90% of that total with 100% or 110% of last year's tax, and take the smaller number.
- Subtract any withholding, then divide what's left by four.
The quarterly tax calculator on this site runs these steps for you using 2026 figures.
How to pay
- IRS Direct Pay from a bank account (free)
- EFTPS, which is useful for scheduling payments in advance
- Your IRS Online Account
- Debit or credit card through an IRS-approved processor (fees apply)
Most states have their own estimated tax system with similar dates.
Frequently asked questions
What if I miss a quarterly payment?
Pay as soon as you can. The penalty is calculated like interest on the amount and number of days you were short, so a late payment is much better than none.
Can W-2 withholding cover my business taxes?
Yes. Withholding is treated as paid evenly through the year, so increasing withholding late in the year can cover a shortfall from earlier quarters.
General information based on federal law for tax year 2026, not tax advice for your situation. State rules vary.