What Is a Quarterly Estimated Tax Payment?

Introduction

Federal income tax generally operates on a pay-as-you-go basis. Employees typically satisfy this requirement through paycheck withholding, while business owners, investors, landlords, retirees, and others with income not adequately covered by withholding may need to make estimated tax payments during the year.

Why Quarterly Tax Payments Matter

Estimated tax payments are advance payments toward an individual’s expected federal tax liability for the year. They may cover federal income tax, self-employment tax, alternative minimum tax, and other amounts that will ultimately be reported on the annual Form 1040.

People commonly make estimated tax payments when they receive income from:

• A sole proprietorship, freelance work, or an independent-contractor business;

• A partnership or S corporation;

• Rental real estate or other investments;

• Capital gains from selling securities, real estate, or a business;

• Interest, dividends, royalties, or prizes;

• Retirement income without sufficient withholding; or

• Bonuses, distributions, or other irregular payments.

Partners and S corporation shareholders may need to make individual estimated payments based on their pass-through income. Corporations are subject to separate estimated-tax rules; the IRS generally identifies corporations expecting to owe at least $500 as potential estimated-tax payers, and corporations do not use Form 1040-ES.

The payments are commonly called “quarterly” tax payments, but the federal payment periods are not four equal calendar quarters. They are installments tied to specific periods and due dates. An estimated tax payment is also not an estimated tax return. Individuals generally use a worksheet to calculate the payment and then apply the payment to the annual Form 1040.

Who Must Pay Estimated Taxes?

As a practical screening rule for 2026, an individual generally must consider estimated payments if both of these conditions apply:

1. The individual expects to owe at least $1,000 in federal tax after subtracting withholding and refundable credits; and
2. Expected withholding and refundable credits will be less than the smaller of:

• 90% of the tax expected to be shown on the 2026 return; or
• 100% of the tax shown on the 2025 return, if the 2025 return covered a full 12 months.

These percentages are modified for certain taxpayers. If 2025 adjusted gross income exceeded $150,000—or $75,000 for married filing separately—the prior-year safe-harbor percentage generally becomes 110%. If at least two-thirds of gross income for 2025 or 2026 is from farming or fishing, the current-year percentage is generally 66⅔% rather than 90%. The farming and fishing test measures gross income from farming or fishing against total gross income from all sources, not merely net business income.

Internal Revenue Code § 6654 provides that an individual generally has four required installments. The required annual payment is generally the lesser of 90% of current-year tax or 100% of prior-year tax, subject to the higher-income and farming-or-fishing rules. The Code also provides an exception when the current-year tax, reduced by the applicable wage-withholding credit, is less than $1,000.

An individual generally does not need estimated payments if the person had no tax liability for 2025, was a U.S. citizen or resident for the entire year, and had a full 12-month 2025 tax year. The person may also avoid separate estimated payments by increasing wage, pension, or other voluntary withholding.

Form 1040-ES and the 2026 Due Dates

What Is Form 1040-ES?

Form 1040-ES—sometimes searched as “1040ES”—is the IRS package individuals use to calculate and pay estimated federal income tax for 2026. The package includes:

• An estimated-tax worksheet;
• Instructions for projecting income, deductions, credits, and tax;
• 2026 tax-rate schedules;
• Payment vouchers for taxpayers paying by check or money order; and
• Guidance on payment methods and special situations.

The official 2026 Form 1040-ES should be used when preparing 2026 payments.

Taxpayers generally do not “file Form 1040-ES online” in the same way they file an annual Form 1040. Instead, they use the Form 1040-ES worksheet to estimate the amount due and submit the payment electronically or by mail. A mailed payment is generally accompanied by the appropriate Form 1040-ES voucher.

2026 Estimated Tax Due Dates

The schedule does not follow equal calendar quarters. The second payment is due June 15 even though calendar-quarter two ends June 30, and the third payment is due September 15 even though calendar-quarter three ends September 30. If a due date falls on a Saturday, Sunday, or legal holiday, payment is generally timely when made on the next business day.

Fiscal-year taxpayers use corresponding dates based on the fourth, sixth, and ninth months of the fiscal year and the first month after the fiscal year ends. Nonresident aliens generally have three installments rather than four, with the first payment due June 15.

September 15 Estimated Tax Payment Deadline

The September 15 payment generally covers income earned from June 1 through August 31. Before making that payment, taxpayers should review changes such as:

• Higher-than-expected business profits;
• Unexpected investment or real estate gains;
• Increased partnership or S corporation income;
• Reduced wage or retirement withholding;
• Large bonuses or distributions; and
• Changes in deductions or credits.

September is also an opportunity to adjust the remaining January payment. Waiting until the annual tax return is prepared may leave too little time to correct an earlier underpayment or manage a large balance due. A tax-planning review before the tax return is prepared can help identify whether the current estimate remains reasonable.

How to Calculate and Pay Quarterly Taxes

How to Calculate Quarterly Estimated Taxes for 2026

A high-level calculation generally follows these steps:

1. Estimate total 2026 income, including wages, business income, rental income, interest, dividends, and capital gains.
2. Subtract applicable adjustments to determine projected adjusted gross income.
3. Apply the expected standard or itemized deductions, qualified business income deduction, and other available deductions.
4. Calculate projected federal income tax.
5. Add self-employment tax and other applicable taxes, including Additional Medicare Tax or net investment income tax when applicable.
6. Subtract expected withholding and refundable credits.
7. Compare the result with the applicable current-year and prior-year safe harbors.
8. Divide or allocate the required amount among the remaining payment dates.

The calculation is not necessarily as simple as dividing projected annual tax by four. Internal Revenue Code § 6654(d) permits an annualized-income installment method when the annualized income installment is less than the regular installment. The applicable percentages for the four installments are 22.5%, 45%, 67.5%, and 90% of annualized tax, reduced by prior required installments.

This method can be useful when income is uneven—for example, when a business earns most of its profits later in the year or an investor realizes a large capital gain in September. Form 2210 and its Schedule AI are generally used when the annualized-income installment method is claimed.

How Adjusted Gross Income Affects the Calculation

Adjusted gross income, or AGI, is generally income after permitted adjustments but before the standard or itemized deduction. Projected AGI can affect tax brackets, deduction and credit limitations, additional taxes, and the safe-harbor percentage that applies to higher-income taxpayers.

For example, the 110% prior-year safe harbor applies when prior-year AGI exceeds $150,000, or $75,000 for married taxpayers filing separately. That threshold measures prior-year AGI—not gross receipts, state-sourced income, or business revenue.

Accurate books and current financial information are particularly important for business owners. A tax-planning review can compare year-to-date income with the prior-year return and identify transactions that may require a new estimate.

How to File Quarterly Taxes

The phrase “how to file quarterly taxes” is common, but individuals generally are making quarterly payments rather than filing four separate individual income tax returns. The usual process is:

1. Estimate the required federal payment.
2. Select the correct tax year and payment type.
3. Submit the payment electronically or mail it with the correct Form 1040-ES voucher.
4. Save the payment confirmation, date, amount, and confirmation number.
5. Provide the payment history to the tax preparer when the annual Form 1040 is completed.

Withholding is generally treated as paid ratably on each installment date unless the taxpayer establishes the actual withholding dates. This rule can make withholding especially valuable late in the year because properly timed withholding may reduce an earlier installment shortfall.

How to Pay Estimated Taxes Online

Federal estimated taxes can generally be paid through:

• An IRS Online Account;
• IRS Direct Pay from a bank account;
• The Electronic Federal Tax Payment System;
• An approved debit, credit-card, or digital-wallet processor; or
• The IRS2Go application.

Before submitting payment, verify the taxpayer, tax year, payment type, amount, and confirmation number. The 2026 Form 1040-ES instructions also state that payments must be made in U.S. dollars and that the IRS cannot accept a single check of $100 million or more.

Federal and North Carolina estimated payments are separate obligations. North Carolina’s individual estimated-tax statute also uses April 15, June 15, September 15, and January 15 installment dates, but it assesses interest under the applicable North Carolina rate rather than the federal § 6621 rate.

Overpayments, Missed Deadlines, and Planning

What Happens If You Overpay Estimated Taxes?

Estimated payments are reconciled on the annual income tax return. If total payments exceed the final tax liability, the taxpayer may generally receive the excess as a refund or apply some or all of it to the following year’s estimated tax payments.

Overpaying is not always inefficient, particularly when income is difficult to predict. However, consistently large overpayments may indicate that withholding or estimated payments should be recalibrated.

What Happens If You Miss an Estimated Tax Deadline?

A missed or insufficient installment may result in an underpayment addition to tax. The addition is generally calculated using the underpayment rate established under § 6621, applied to the amount underpaid for the period beginning on the installment due date and ending when the amount is paid or the annual return due date is reached.

Paying the full balance with the annual return does not necessarily eliminate an earlier installment underpayment. The addition may be avoided or reduced through a safe harbor, annualized-income calculation, timely withholding, or a statutory waiver. Waivers may apply for casualty, disaster, or unusual circumstances, and for certain newly retired or disabled taxpayers when reasonable cause and absence of willful neglect are established.

An ordinary estimated-tax shortfall is not automatically fraud. Separate civil fraud penalties can apply when an underpayment is due to fraud, and willful tax evasion or willful failure to file or pay can result in criminal prosecution.

How Tax Planning Can Improve Estimated Payments

Estimated payments should be based on the taxpayer’s expected 2026 position, not simply copied from last year’s return. Proactive planning can help:

• Project annual taxable income;
• Monitor business profits and owner compensation;
• Account for large transactions and capital gains;
• Coordinate federal and state payments;
• Evaluate withholding alongside estimated payments;
• Update calculations when income changes; and
• Reduce the risk of a large unexpected balance at tax time.

A tax advisor can also help business owners, investors, landlords, and high-income individuals determine whether regular installments, increased withholding, or an annualized-income approach best fits their circumstances.

Frequently Asked Questions

• Are estimated tax payments required every quarter?

  • Not necessarily. The answer depends on expected tax, withholding, credits, income timing, and applicable exceptions.

• What is the difference between Form 1040 and Form 1040-ES?

  • Form 1040 is the annual individual income tax return. Form 1040-ES provides the worksheet, instructions, and vouchers used to calculate and make estimated payments.

• Can I pay estimated taxes online?

  • Yes. IRS Direct Pay, an IRS Online Account, EFTPS, card processors, and IRS2Go are among the available options.

• Do I still file Form 1040 if I make estimated payments?

  • Yes. Estimated payments are advance payments and are reconciled on the annual Form 1040.

• Can I make one estimated payment instead of four?

  • You can pay the projected annual amount early. However, paying the entire balance only when the annual return is filed may not eliminate penalties for earlier installment underpayments.

• Do quarterly payments have to be equal?

  • No. Payments may differ when income changes during the year, particularly when the annualized-income installment method is appropriate.

• Do estimated tax payments include state taxes?

  • Federal and state estimated taxes are separate. A North Carolina taxpayer may need to make payments to both the IRS and the North Carolina Department of Revenue.

Conclusion

The 2026 estimated tax payments are due April 15, June 15, September 15, and January 15, 2027, subject to weekend, holiday, fiscal-year, and special taxpayer rules. Form 1040-ES helps individuals calculate the required amount, but the correct payment often depends on current income, withholding, deductions, credits, and safe-harbor rules.

Estimated payments should reflect more than last year’s tax return. Changes in business income, investments, compensation, deductions, and other financial circumstances can materially affect the amount owed. A year-round planning review can help taxpayers make timely payments and avoid an unwelcome surprise when the annual return is filed.