Free tool
Know your quarterly estimated payment.
A planning estimate of what to send the IRS each quarter, based on your expected net profit.
Covers self employment tax plus a rough federal income estimate.
Set aside each quarter
$4,000
Estimated tax for the year
$16,000
Due Apr 15 · Jun 15 · Sep 15 · Jan 15
Estimate only: not tax, legal, or financial advice, and provided with no warranty of accuracy. The IRS safe-harbor rule lets you avoid the underpayment penalty by paying the lower of (a) 100% of prior year’s total tax (110% at higher income), or (b) 90% of current year’s actual tax. Quarterly due dates are typically April 15, June 15, September 15, and January 15 of the following year. Verify with a licensed tax professional before relying on these numbers for actual payments.
How the math works
Two targets, and you pay the lower one.
- The prior year target. 100% of last year’s total tax, or 110% if your prior year AGI was over $150,000. Fixed and predictable: divide by four and you are penalty safe no matter what this year does.
- The current year target. 90% of what you will actually owe this year. The calculator projects it by annualizing your year to date profit, then computing SE tax plus federal and state income tax on the projection with the 2026 tables. The SE tax calculator shows that full year math in detail.
- Worked example. If last year’s total tax was $12,000 and your AGI was under $150,000, the safe harbor is $12,000, so $3,000 per deadline. If this year’s projection says you will only owe $9,000, the 90% target is $8,100, or $2,025 per deadline, and the calculator recommends the lower path.
- What it does not model. W2 withholding from a day job or spouse (that counts toward the targets), the Form 2210 annualized method for lumpy income, and state estimated payment schedules, which several states run separately.
FAQ
Common questions.
- Do I have to pay quarterly estimated taxes?
- Generally yes if you expect to owe at least $1,000 in tax for the year after withholding and credits, which covers most full time self employed vendors. Skipping payments does not change what you owe in April; it adds an underpayment penalty on top.
- When are the 2026 quarterly payments due?
- The four deadlines for tax year 2026 are April 15, June 15, and September 15 of 2026, and January 15 of 2027. When a date falls on a weekend or holiday it moves to the next business day.
- What is the safe harbor rule?
- You avoid the underpayment penalty if your estimated payments reach the lower of two targets: 100% of last year's total tax (110% if your prior year adjusted gross income was over $150,000), or 90% of what you will actually owe this year. Paying the prior year target is the predictable path because the number is fixed the day you file.
- What happens if my income is irregular?
- The safe harbor based on last year's tax still works: it is the same fixed amount each quarter no matter how lumpy this year is. The IRS also allows an annualized method on Form 2210 Schedule AI that matches payments to when income actually arrived, which this calculator does not model.
Educational estimate, not tax advice. Safe harbor rules per IRS Form 1040-ES and Publication 505 for tax year 2026; SE tax and bracket figures per IRS Topic 751 and Rev. Proc. 2025-32. Talk to a CPA about your situation, especially with mixed W2 and self employment income.
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