Quarterly Estimated Tax Calculator 2026

What are quarterly estimated taxes?

The U.S. tax system is pay-as-you-go. Employees pay through paycheck withholding; anyone with income that isn’t withheld on — freelance and 1099 work, a side business, rental income, investment gains, alimony from pre-2019 divorces — is expected to send money to the IRS during the year using Form 1040-ES. Those four installments are your quarterly estimated taxes. They cover both income tax and self-employment tax.

You generally must make estimated payments if you expect to owe $1,000 or more when you file, after subtracting withholding and refundable credits. Skip them and the IRS adds an underpayment penalty, figured like interest on each late installment.

How to use this quarterly estimated tax calculator

1. Enter this year’s expected income. Best guesses are fine — you can re-run the numbers each quarter as the year unfolds. Include business expenses so the calculator works from net profit.
2. Add withholding and payments. If you or your spouse have a W-2 job, withholding counts toward your required payments, and the IRS treats it as paid evenly through the year no matter when it was taken out.
3. Enter last year’s total tax and AGI. That’s Form 1040 line 24 (total tax) and line 11 (AGI) from your 2025 return. These unlock the prior-year safe harbor, which is usually the easiest way to guarantee no penalty.
4. Choose a plan. “Minimum to avoid a penalty” pays the safe-harbor amount; “Pay the full projected tax” aims for a $0 balance in April.

Safe-harbor rules: how much you must pay

You won’t owe an underpayment penalty if your withholding plus timely estimated payments reach the smaller of these two amounts — called the required annual payment:

The prior-year test is popular because you know the number in advance. Even if your income doubles this year, paying 100% (or 110%) of last year’s tax in four equal installments means no penalty — you simply settle the rest when you file.

Do I have to pay quarterly taxes my first year?

It depends on what you owed last year — not on whether this is your first year self-employed. The tax code has a specific exception (Internal Revenue Code §6654(e)(2)): you owe no underpayment penalty for this year if all three of these are true:

1. You had no total tax liability for last year (Form 1040 line 24 was zero, or you weren’t required to file),
2. last year was a full 12-month tax year, and
3. you were a U.S. citizen or resident for all of last year.

“No liability” means zero tax, not “I got a refund.” Many people starting a business had a W-2 job last year and paid tax through withholding. They don’t qualify for the first-year exception, but they get something nearly as good: the prior-year safe harbor. If last year’s total tax was $4,000, paying $4,000 this year ($1,000 a quarter, or a mix of withholding and estimates) protects you from penalties no matter how much your new business earns.

To check it here, enter 0 as last year’s total tax and keep the 12-month box ticked; the calculator will flag the exception and still show what to set aside.

Worked example

A single freelancer expects $85,000 of 1099 income and $15,000 of expenses in 2026 (net profit $70,000), with no W-2 job. Last year’s total tax was $9,000 and AGI was $60,000.

Paying $2,250 on each due date avoids any penalty. To owe nothing in April instead, the freelancer would pay $3,586 a quarter.

2026 estimated tax due dates

The four “quarters” aren’t equal three-month periods. When a date falls on a weekend or legal holiday, the deadline moves to the next business day.

You can skip the January payment if you file your 2026 return and pay the full balance by February 1, 2027. Farmers and fishermen can make a single payment by January 15 or file and pay by March 1.

Uneven income? The annualized installment method

The standard rules assume you earn evenly and pay 25% each quarter. If most of your income arrives late in the year — a big Q4 contract, a December capital gain — you can use the annualized income installment method on Form 2210, Schedule AI. It sizes each installment to the income you actually earned by the end of that period, so smaller early payments aren’t penalized. You must attach Schedule AI to your return to claim it. This calculator uses equal installments; if your income is lumpy, treat the early-quarter numbers as conservative.

How to pay estimated taxes

• IRS Direct Pay — free bank transfer at irs.gov/payments; choose “Estimated Tax” and Form 1040-ES.
• Your IRS Online Account — schedule payments and see what’s been credited.
• EFTPS — the Treasury’s free system, useful for scheduling a full year of payments in advance.
• Debit or credit card through an IRS-approved processor (a fee applies), or a check with the 1040-ES voucher.
• Increase W-2 withholding — if you also have a job, extra withholding on a new W-4 counts as paid evenly through the year, which can cure an early-quarter shortfall.

What if you miss a payment?

The underpayment penalty is calculated separately for each installment, using the IRS underpayment interest rate (the federal short-term rate plus 3 percentage points), from the due date until you pay or until April 15. Paying late is still better than not paying, because the penalty stops growing once the shortfall is made up. Read more in Quarterly Taxes 101, estimate your full-year bill with the 1099 tax calculator, or check withholding with the paycheck calculator.