Required annual payment
Safe-harbor target = the smaller of 90% of expected current-year tax or 100% of prior-year tax (110% for certain higher-income taxpayers), less expected withholding.
The guided inputs calculate an expected federal income-tax and self-employment-tax total before applying safe-harbor percentages. A prior-year Form 1040 is optional, not required.
The statutory quarters are not equal calendar quarters, and due dates can move for weekends, holidays or disaster relief. Always verify the current IRS schedule.
Assumptions and limits
- Prior-year return covered 12 months
- Four equal installments
- No farmer/fisher special rule
- Federal payments only
Tax law depends on facts this tool cannot collect. Do not use the result as the sole basis for filing, withholding or payment decisions.
Frequently asked questions
Which safe-harbor method does the calculator use?
It uses the smaller of 90% of expected current-year tax or the applicable prior-year percentage, then subtracts expected withholding.
When does 110% apply?
For 2026, the prior-year percentage generally becomes 110% when 2025 AGI exceeded $150,000, or $75,000 if filing separately.