Quarterly estimated taxes: who pays, the four 2026 dates, and the safe harbor
Nobody withholds tax from freelance income, so the IRS expects it in four installments. Miss them and the penalty is interest, charged from the date each one was due.
An employee's tax is paid as they go: a slice of every paycheck goes to the Treasury before it reaches them. Freelance and side-business income has no such slice. The IRS's answer is to require the taxpayer to send it in four instalments across the year.
Who has to
Anyone who expects to owe $1,000 or more in federal tax for the year after subtracting withholding and credits. That threshold is low: at the 30% combined rate worked through in the side-income guide, about $3,300 of profit gets there.
The rule is about total tax paid during the year, not about which income it came from. Someone with a salary can cover the tax on side income by raising the withholding on the salary — a new Form W-4 to the employer — instead of sending separate payments. The IRS treats withholding as paid evenly through the year, whenever it actually happened.
The 2026 dates
| Instalment | Covers income from | Due |
|---|---|---|
| First | January 1 – March 31, 2026 | April 15, 2026 |
| Second | April 1 – May 31, 2026 | June 15, 2026 |
| Third | June 1 – August 31, 2026 | September 15, 2026 |
| Fourth | September 1 – December 31, 2026 | January 15, 2027 |
The uneven periods matter. Someone who earns most of their side income in the summer is expected to have paid on it by September 15, not at the end of the year.
How much: the safe harbor
The penalty for underpaying is avoided if payments during the year reach any one of three marks:
- 90% of the tax that turns out to be owed for 2026, or
- 100% of the tax shown on the 2025 return, or
- 110% of the 2025 tax, if 2025 adjusted gross income was above $150,000.
Nobody knows their current-year tax in April. Last year's tax is a number on a filed return. Paying a quarter of it each instalment is a defined target that cannot be missed by an unlucky guess — and if income rises, the balance is simply paid in April 2027 without penalty.
A worked example
Take someone whose 2025 return showed $9,000 of total tax, with $6,000 withheld from a salary. To sit inside the 100% safe harbor for 2026 they need $9,000 paid during the year. Withholding covers $6,000, so the estimated payments need to total $3,000 — $750 per instalment. Illustrative figures.
The penalty for missing is not a fine in the usual sense. It is interest on the shortfall from the date each instalment was due, at a rate the IRS sets each quarter. It is charged even if the full balance is paid on time in April.
Sources
- Estimated taxesInternal Revenue Service · checked Sep 24, 2026
- Topic no. 306, Penalty for underpayment of estimated taxInternal Revenue Service · checked Sep 24, 2026