Estimated tax penalty: how it works and how to avoid it

If you work for yourself, the IRS expects you to pay tax during the year, in four estimated tax payments. If a payment is too small or late, the IRS can charge an estimated tax penalty.

The word “penalty” sounds scary, but this one works like interest. It is usually small, and it is easy to avoid once you know how it works.

How the penalty works

The IRS looks at each of your four payments. For each one that was short or late, it charges a small amount for every day the money was missing. The rate is the IRS underpayment rate: 7% a year for October to December 2026 (IRS).

At 7%, $1,000 that is late costs about 19 cents a day. So the sooner you pay, the less it costs.

This penalty is separate from the penalties for filing your return late or not paying your bill in April.

An example

Sam is a freelance developer. (He is an example, not a real person.) His June 15, 2026 payment should have been $5,000. A client paid him late, so he sent only $3,000. He paid the missing $2,000 on September 15.

That is annoying, but small. The longer a payment stays short, the more it grows.

The IRS rates for 2026 were 7% (January to March), 6% (April to June), 7% (July to September) and 7% (October to December) (IRS).

Three rules to know

1. Each payment counts on its own. You can owe a penalty for April even if you paid extra in September, and even if you get a refund (Instructions for Form 2210).
2. A payment fills the oldest gap first. If Sam sends his usual $5,000 in September, $2,000 of it goes to June. That leaves September $2,000 short, and a new penalty starts. To catch up, pay the missing amount on top of the normal payment.
3. The clock stops when you pay, or on the April due date the next year, whichever comes first.

When you owe no penalty

You owe no penalty if one of these is true:

• You paid the safe harbor amount on time. That is last year’s total tax, split into four payments (110% if last year’s AGI was over $150,000). See our safe harbor guide.
• You owe less than $1,000 after withholding when you file (Instructions for Form 2210).
• You had no tax last year, were a US citizen or resident all year, and last year was a full 12 months.

Do I need to fill in a form?

Usually not. The IRS works out the penalty and sends you a letter. It says most people should not file Form 2210 (Instructions for Form 2210).

You do need Form 2210 if you want to:

• Ask the IRS to remove the penalty. This can be possible after a disaster or other unusual event, or if you retired after age 62 or became disabled and had a good reason (IRS). For federally declared disasters, the IRS usually gives relief on its own.
• Show that your income came late in the year. Schedule AI on Form 2210 can lower the early payments you owed.

Ways to keep it small

• Pay as soon as you can. Every day counts, so a late payment is better than a later one.
• Have more tax taken from a paycheck. If you or your spouse have a W-2 job, extra withholding counts as if it was paid evenly all year. It can cover earlier gaps.
• Use the safe harbor. Pay last year’s tax in four equal payments, on time, and the penalty cannot apply.

Most penalties come from a forgotten date. Righto can remind you of each federal estimated tax date and add the dates to your calendar. See vendors and reminders. Our estimated tax due dates page also has every date.

If you get a penalty letter you do not understand, a tax professional can help.

What to do now

1. Add up what you have paid toward 2026 so far.
2. Work out what you should have paid by now: one quarter of your yearly amount for each due date that has passed.
3. If you are short, pay the difference now. Choose “estimated tax” and tax year 2026 (how to pay online).
4. Put January 15, 2027 in your calendar.

Righto is free, easy to use and needs no account.

Sources

• Underpayment of estimated tax by individuals penalty, IRS
• Instructions for Form 2210 (2025), IRS
• Quarterly interest rates, IRS
• Interest rates remain the same for the fourth quarter of 2026 (IR-2026-98), IRS