Finance
Quarterly Estimated Tax Calculator
If you expect to owe $1,000+ at tax time, the IRS wants quarterly estimated payments. This calculator combines income tax and self-employment tax, subtracts withholding, and splits the rest across four quarters.
Quick answer: If you'll owe $1,000+ at filing, the IRS wants quarterly payments; pay the smaller of 90% of this year's tax or 100% of last year's to avoid a penalty.
How it works
1. Project your annual tax
Estimate your total income for the year, including self-employment, investment, and other untaxed income, then compute the income tax plus self-employment tax you expect to owe. This annual figure is the basis for your quarterly payments. Revisit it midyear if income changes.
2. Meet a safe-harbor target
To avoid an underpayment penalty, pay at least 90% of this year's tax or 100% of last year's tax (110% if your prior-year adjusted gross income was over $150,000). Hitting either safe harbor protects you even if you end up owing more at filing. The lower of the two is usually the easier target.
3. Pay on the four due dates
Estimated taxes are due roughly April 15, June 15, September 15, and January 15 of the following year. Divide your target by four, or pay more in quarters when income is higher. The calculator splits the total into the four installments so you can budget each payment.
Frequently asked questions
Who has to pay quarterly estimated taxes?
Anyone who expects to owe $1,000 or more after withholding — typically freelancers, contractors, and investors without enough tax withheld from a paycheck.
What is the safe-harbor rule?
You avoid an underpayment penalty by paying the smaller of 90% of this year's tax or 100% of last year's (110% if last year's AGI exceeded $150,000).
When are the payments due?
Generally April 15, June 15, September 15, and January 15 of the following year. The calculator splits your net owed evenly across the four.