Estimated Taxes: The Safe Harbor Rules
Published October 29, 2026
A safe harbor is a rule that protects you from the underpayment penalty. If your payments during the year add up to enough, you avoid the penalty even if you owe tax when you file. This post covers the rules. For the payment calendar and a freelancer's routine, see Quarterly Estimated Taxes for Freelancers. IRS: Estimated taxes
Step 1: Do you have to pay?
Generally, you must make estimated payments if you expect to owe $1,000 or more when you file, after withholding and refundable credits. Income that often has no withholding includes self-employment income, interest, dividends, capital gains, alimony, and prizes. If you run your own business, you generally need to make estimated payments.
Step 2: Find your safe harbor amount
Your payments must add up to at least the smaller of these two amounts:
- 90% of this year's tax. This is the tax shown on this year's return.
- 100% of last year's tax. This is the tax shown on last year's return.
The last-year figure rises to 110% if your adjusted gross income (AGI) for last year was more than $150,000. If you file as married filing separately, the line is $75,000. Last year's return must cover all 12 months.
Step 3: Check an example
Illustration only, with round numbers. Priya has no tax withheld from her pay this year. Last year her tax was $4,000 and her AGI was $52,000. This year she expects to owe $10,000.
Her safe harbor amount is the smaller of two figures. 90% of this year's tax is $9,000. 100% of last year's tax is $4,000. The smaller figure is $4,000, so Priya's estimated payments need to total at least $4,000 for the year. One way to split that is four payments of $1,000.
Priya still owes the rest when she files. Paying the safe harbor amount protects her from the penalty, but it does not cancel the tax she owes.
Step 4: Know how the penalty is figured
Form 2210 shows whether you owe the underpayment penalty. The IRS generally figures the penalty for you, so in many cases you do not need to file Form 2210.
The IRS may waive the penalty in some cases, such as after a casualty, a disaster, or another unusual circumstance, or if you retired after age 62 or became disabled. The Form 2210 instructions explain how to request a waiver.
Step 5: Adjust when income comes in unevenly
Figure your estimate again when your income changes. If you estimated too high or too low, complete another Form 1040-ES worksheet and adjust the payments that remain. If your income comes in unevenly, for example from a large sale late in the year, you may be able to lower the penalty by annualizing your income and making uneven payments. This method uses Form 2210 and its annualized income schedule.
How to pay
You can pay estimated tax online, by Direct Pay from your bank account, by phone, or with the IRS app. You can also mail a payment with Form 1040-ES. You may pay more often than once a quarter, as long as you have paid enough by the end of each quarter.
Weekends and holidays
If a due date falls on a Saturday, Sunday, or legal holiday, the payment is on time if you make it on the next day that is not a weekend or holiday.
Where self-employment tax fits
If you are self-employed, your estimate covers self-employment tax as well as income tax. See Self-Employment Tax: The Basics of Schedule SE for how that tax is figured.
Your checklist
- Check whether you expect to owe $1,000 or more after withholding and credits.
- Find 90% of this year's tax and 100% (or 110%) of last year's tax. Pay at least the smaller number.
- Check whether last year's AGI passed $150,000 ($75,000 if married filing separately).
- If income comes in unevenly, consider annualizing with Form 2210.
- Figure your estimate again when your income or deductions change.
This page is general information, not advice for your return. Publication 505, Tax Withholding and Estimated Tax, has the full worksheets and the special rules for farmers, fishermen, and certain higher-income taxpayers.
Sources: IRS: Estimated taxes (https://www.irs.gov/businesses/small-businesses-self-employed/estimated-taxes); IRS: Estimated tax FAQs (https://www.irs.gov/faqs/estimated-tax); IRS: Instructions for Form 2210 (https://www.irs.gov/instructions/i2210); IRS: Publication 505, Tax Withholding and Estimated Tax (https://www.irs.gov/publications/p505) This is general information, not advice about your specific return.
