The next federal estimated tax payment is due September 15, 2026. If you are self-employed and expect to owe $1,000 or more for the year, this is a payment you are supposed to make, and missing it costs interest rather than a fine.

Quarterly estimated tax is the part of self-employment nobody warns you about properly. An employer withholds tax from every paycheck and sends it in on your behalf, four times a year, on a schedule you never see. Work for yourself and you inherit that job. The IRS still wants the money through the year, not in one lump in April.

The four dates

They are not evenly spaced, which catches people out. The second period is two months long, the fourth is four.

2026 federal estimated tax deadlines

The periods are uneven. The dates are not negotiable.

JAN – MAR APR – MAY JUN – AUG SEP – DEC 15 APR 2026 15 JUN 2026 15 SEP 2026 15 JAN 2027 ▲ NEXT
Each payment covers the income you earned in the period above it — so the September payment is for what you made in June, July and August, not for what you are earning now.
Two people sitting across a small cafe table, one pointing at a single sheet of paper between them.
The safe-harbor number comes off last year’s return, which means it is knowable in advance and worth having someone confirm once. After that it is arithmetic you can do yourself.

The safe harbor is the part worth knowing

Most people believe they have to predict this year’s income accurately and pay tax on the prediction. On irregular income that is close to impossible, and it is not actually the rule.

You avoid the underpayment penalty entirely if your payments and withholding for the year add up to at least the smaller of:

That second option is the useful one. It is a number you already know, printed on a return you already filed. Pay it in four installments and the penalty cannot reach you even if this year turns out to be your best ever and you end up owing far more. You will settle the difference in April, without interest.

For anyone whose income swings, this converts an impossible forecasting problem into arithmetic: take last year’s tax, divide by four, pay it on the dates.

What missing one actually costs

It is not a fine and it is not a black mark. It is interest, charged at the federal short-term rate plus three percentage points — recently around 7% a year — running from the date the payment was due until you pay it or until the following April, whichever comes first.

So a $2,000 payment made three months late costs somewhere near $35. Worth avoiding, not worth panicking over. The useful consequence of knowing this: if you are short on the day, pay what you can rather than nothing. The interest is charged on the shortfall, so a partial payment reduces it proportionally.

A man standing at a kitchen island late in the evening with a laptop open in front of him and a mug beside it, the house dark around him.
Paying a quarterly estimate takes about four minutes and no paperwork. The difficulty was never the payment — it is remembering the date, which is why it belongs in a calendar rather than in your head.

Paying it

IRS Direct Pay takes a payment straight from a bank account with no fee and no account to set up — it is the shortest path for most people. EFTPS is the alternative and is worth enrolling in if you would rather schedule payments in advance, though enrollment takes a few days, so it is not the answer if the deadline is close. Card payments work and carry a processing fee.

Whichever you use, make sure the payment is labeled as estimated tax for the right year. A payment applied to the wrong year is a genuinely tedious thing to unpick.

The connection to setting money aside

Quarterly payments are only painful if the money has to be found on the day. If a percentage of every payment has been moving out of your spendable balance as it arrives, the deadline is an administrative task rather than a financial event.

That is the entire argument for setting aside per payment rather than per quarter — the quarterly date stops being the thing you save up for and becomes the thing you transfer on.

What to do this week

  1. Find your 2025 return and the total tax figure on it. Divide by four. That is your safe-harbor installment.
  2. Check whether your 2025 AGI was over $150,000 — if so the multiplier is 110%, not 100%.
  3. Pay before September 15. If you cannot pay all of it, pay part of it.
  4. Put the January date in a calendar now, because the fourth payment is the one people forget. It lands in the middle of the holidays and covers four months.

Questions, answered

When are quarterly taxes due in 2026?

The federal estimated tax deadlines for the 2026 tax year are April 15, 2026; June 15, 2026; September 15, 2026; and January 15, 2027. The periods they cover are uneven: the June payment covers only April and May, while the January payment covers September through December.

What is the estimated tax safe harbor?

You avoid the underpayment penalty if your payments and withholding total at least the smaller of 90 percent of your current-year tax or 100 percent of your prior-year tax. That rises to 110 percent of prior-year tax if your prior-year adjusted gross income was over $150,000, or $75,000 if married filing separately. Paying the prior-year figure is useful on irregular income because it is a number you already know.

What happens if I miss a quarterly tax payment?

It is interest, not a fine. The underpayment charge is the federal short-term rate plus three percentage points, recently around 7 percent a year, and it runs from the due date until you pay or until the following April, whichever comes first. If you cannot pay the full amount on the day, pay part of it, because the interest is charged on the shortfall.

Do I have to pay estimated tax if I am self-employed?

Generally yes, if you expect to owe $1,000 or more in tax for the year after subtracting withholding and credits. Nobody is withholding tax from your income on your behalf, so the estimated payments are how the money reaches the IRS through the year.

Sources

  1. Estimated taxes — IRS. Who has to pay, the $1,000 threshold, and the payment periods.
  2. Publication 505, Tax Withholding and Estimated Tax — IRS. The safe-harbor rules in full, including the 110% threshold for higher AGI.
  3. Form 1040-ES, Estimated Tax for Individuals (PDF) — IRS. The worksheet, and the vouchers if you pay by mail.
  4. Direct Pay with bank account — IRS. The no-fee way to pay, with no enrollment step.
  5. Penalties — IRS. How the underpayment interest is calculated and when it stops running.

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General information, not tax advice. The dates and rules here are federal and were checked against the IRS on September 4, 2026; state estimated tax deadlines and rules differ and are not covered. Whether the safe harbor is the right approach for your situation, and what your prior-year figure actually is, are questions for an accountant.