Quarterly Tax Calculator
Estimate your quarterly estimated tax payments with exact IRS deadlines. Use the safe harbor rule to avoid underpayment penalties.
Quarterly payment schedule
Annual summary
Worked example
On $80,000 net income, your total annual tax is $20,334.6. Divide by 4 for quarterly payments of $5,083.65. Pay this amount each quarter by the deadline to avoid penalties.
How this calculator works
The calculator estimates your total annual tax (SE + federal income) and divides it by 4 for quarterly payments. If you enable the safe harbor rule and enter your prior year tax, it uses 100% of last year's tax (110% if AGI > $150K) as the required annual payment.
What affects your payments
- Quarterly due dates: April 15, June 15, September 15, January 15
- You must pay estimated taxes if you expect to owe $1,000+ for the year
- Use the safe harbor rule: pay 100% of prior year tax (110% if AGI > $150k)
- Underpayment penalties are based on the shortfall amount and duration
Frequently asked questions
Do I have to pay quarterly estimates?
If you expect to owe $1,000 or more in taxes for the year after subtracting withholding and credits, the IRS requires quarterly estimated payments. Most freelancers qualify.
When are quarterly estimated taxes due in the US?
Quarterly payments are due on April 15, June 15, September 15, and January 15 of the following year. If a due date falls on a weekend or holiday, it moves to the next business day.
What is the safe harbor rule?
If you pay at least 100% of your prior year tax liability (110% if your AGI was over $150,000), you won't owe underpayment penalties regardless of how much you actually owe this year.
How much should I pay each quarter?
A reliable approach is to estimate your total annual tax and divide by 4, or to use the safe harbor amount of 100% (or 110%) of last year's tax, split four ways. This calculator gives you both.
What if I miss a deadline?
Penalties accrue from the due date. You can use IRS Form 2210 to calculate the penalty, or pay as soon as possible to minimize it. The penalty is essentially interest on the unpaid amount.
What's the penalty for not paying quarterly taxes?
The underpayment penalty is effectively interest on the amount you should have paid, calculated from the due date. It's typically around 3–4% annually and can be avoided with the safe harbor rule.