Guide topic
Quarterly and estimated taxes
The four payments a year that nobody warns you about until you owe a penalty.
United States only. These guides cover US federal tax. They do not apply to Canada, the UK or other countries.
Employees have tax taken out of every paycheque. Nobody does that for you, so the IRS asks you to do it yourself in four instalments across the year. Miss them and the penalty is not a fine for being late — it is interest, charged from each due date, which is why it keeps growing quietly until you pay.
The good news is that the rule you actually have to satisfy is mechanical, not a guess about what you will earn. Pay a set percentage of last year’s total tax — the safe harbour — and you cannot be penalised no matter how the year turns out. That single rule removes most of the anxiety from this topic, and it is the one thing worth understanding before anything else here.
Uneven income complicates it, and there is a separate method for that. Missing a payment is recoverable, and the guide on it explains why paying late is still much better than waiting for April.
5 guides, in the order they usually matter
- Quarterly estimated taxes: a plain guide for the self-employed Who has to pay, the 2026 due dates, how to work out each payment, how to send it, and what happens if you skip one.
- How much should you set aside for taxes as a freelancer? The 30% rule overshoots at almost every income level. What the 2026 arithmetic actually says, and when 30% stops being enough.
- The safe harbour rule: how to never owe an underpayment penalty Pay 100% of last year's tax and you are protected from the penalty regardless of what you earn this year. The most useful rule in freelance tax.
- Estimated taxes when your income is wildly uneven Paying a flat quarter punishes anyone with a lumpy year. The annualised method lets you pay what you actually earned, quarter by quarter.
- You missed a quarterly tax payment. What actually happens now There is no fine for missing one. The penalty is interest, it is smaller than people fear, and there is a way to erase it entirely.