Quarterly Estimated Tax Calculator

Project your annual self-employment and income tax, then split it into four quarterly payments so you're never surprised by a penalty.

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Estimated Annual SE Tax—
Estimated Annual Income Tax—
Total Estimated Annual Tax—
Payment Due Each Quarter—
📊 This is a simplified estimate for planning purposes. It doesn't account for tax brackets, deductions beyond the SE tax adjustment, credits, or state taxes. Use IRS Form 1040-ES or a tax professional for a precise figure.

2026 Quarterly Payment Due Dates

QuarterIncome Period CoveredDue Date
Q1Jan 1 – Mar 31April 15
Q2Apr 1 – May 31June 15
Q3Jun 1 – Aug 31September 15
Q4Sep 1 – Dec 31January 15 (following year)

Missing a quarterly payment (or underpaying significantly) can trigger an IRS underpayment penalty, even if you pay your full balance by the April filing deadline. Setting aside a consistent percentage of each payment you receive is the most reliable way to stay ahead of these deadlines.

The Safe Harbor Rule

You generally avoid an underpayment penalty if, across the year, your withholding and timely estimated payments add up to at least 90% of what you'll owe for the current year, or 100% of what you owed last year (110% if your prior-year adjusted gross income was above $150,000, or $75,000 if married filing separately). Many self-employed people use last year's total tax as a simple, conservative planning floor and adjust up if this year's income is running higher.

Worked Example

$90,000 expected profit, 15% estimated income tax rate

Taxable SE income: $90,000 × 92.35% = $83,115.
SE tax: ($83,115 × 12.4%) + ($83,115 × 2.9%) = $12,717.
Income tax: ($90,000 − half of SE tax) × 15% ≈ $12,546.
Total annual estimate: ≈ $25,263.
Per-quarter payment: ≈ $6,316.

Frequently Asked Questions

Can I pay unequal amounts each quarter?

Yes — the IRS allows the annualized income installment method for uneven income instead of four identical payments.

Does this include Additional Medicare Tax?

No — check that separately with our Additional Medicare Tax Calculator.

What if I also have a W-2 job?

W-2 withholding counts toward your total tax paid and can reduce what you owe quarterly — this planner doesn't net that out automatically, so subtract it manually.

Related Tools & Guides

Self-Employment Tax Calculator · Additional Medicare Tax Calculator · Quarterly Estimated Taxes: A Complete Guide · Full FAQ

Sources: IRS — Estimated Taxes · IRS — About Form 1040-ES. This tool provides estimates only — see our Disclaimer.