How to File Form 1040-ES: Safe Harbor, Due Dates, Payment

To file Form 1040-ES, you work through the worksheet in the form’s package to figure out your total estimated tax for the year, divide that by four, and send each installment to the IRS by its quarterly deadline using Direct Pay, your IRS Online Account, or a mailed payment voucher. The form itself is short: the worksheet stays with your records, and only the voucher (if you pay by mail) goes to the IRS. Most of the work is the calculation.

Do You Actually Need to File It

You owe estimated taxes for 2026 only if both of these are true: you expect to owe at least $1,000 in tax after withholding and refundable credits, and you expect withholding and credits to cover less than the smaller of 90% of your 2026 tax or 100% of your 2025 tax.¹ If your withholding already gets you past one of those thresholds, you don’t need to file 1040-ES at all.

One exception zeros you out entirely: if you had no tax liability last year, were a U.S. citizen or resident all year, and your prior tax year covered a full 12 months, you owe nothing in estimated payments this year no matter what you earn.²

Calculating Your Required Annual Payment

Your required payment for the year is the lower result from two methods. Pay that amount, split across four installments, and you avoid a penalty.

Prior Year Safe Harbor

The simpler method is to base payments on last year’s actual tax. If your 2025 adjusted gross income was $150,000 or less ($75,000 or less if married filing separately), paying 100% of your 2025 tax across four installments satisfies the safe harbor.¹ Above those AGI thresholds, the safe harbor rises to 110% of your 2025 tax.³ The number you’re working from already exists on the return you filed, which is why this is the path of least resistance.

Current Year Method

The other route is to project your 2026 income, deductions, credits, and self-employment tax, then pay at least 90% of the resulting tax.¹ This gives a better number when your income has dropped from a strong prior year, since the safe harbor would leave you overpaying all year.

If you have self-employment earnings, factor in the 15.3% self-employment tax (12.4% Social Security and 2.9% Medicare), calculated on 92.35% of your net earnings, with the Social Security portion capped at the 2026 wage base of $184,500.⁴⁵

Uneven Income: The Annualized Method

If your income arrives in lumps rather than steadily — a seasonal business, a property sale, a late-year contract — dividing your annual estimate into four equal payments can force you to overpay early. The annualized income installment method sizes each quarter’s payment to the income you actually earned during that period. You use Schedule AI on Form 2210 to run the calculation and attach the form to your annual return to explain the uneven payments.⁶

Filling Out the Worksheet and Voucher

The 1040-ES package contains a worksheet that walks through the calculation above. Plug in your expected income, deductions, credits, and self-employment tax to arrive at total estimated tax for the year. The worksheet stays with your records. You never send it to the IRS.

What you do send, if paying by mail, is one of the four payment vouchers included in the package. Each voucher asks for your name, mailing address, Social Security number, the tax year, and the payment amount.¹ Filing jointly? Include both names and both SSNs. The vouchers are numbered 1 through 4; use the one matching the quarter you’re paying.

If you made estimated payments last year, the IRS may mail you a package with your name and SSN already printed on the vouchers. Check the details and correct anything that has changed. If you pay electronically, the voucher isn’t needed at all.

2026 Due Dates

Estimated taxes don’t split the year into equal quarters. For 2026 calendar-year taxpayers:

April 15, 2026 — for income earned January 1 through March 31
June 15, 2026 — for income earned April 1 through May 31
September 15, 2026 — for income earned June 1 through August 31
January 15, 2027 — for income earned September 1 through December 31

All four 2026 dates fall on weekdays with no holiday conflicts. When a due date does land on a weekend or legal holiday in other years, it moves to the next business day.⁷ Fiscal-year filers pay on the 15th day of the 4th, 6th, and 9th months of the fiscal year, plus the 1st month of the next fiscal year.⁸

Notice that the second period covers only two months. The June 15 deadline arrives faster than most first-time filers expect.

How to Submit Payment

IRS Direct Pay

Direct Pay pulls the payment from your checking or savings account with no fee and gives you an immediate confirmation number.⁹ Choose “Estimated Tax” as the payment reason and select the tax year and quarter. Individual payments through Direct Pay can’t exceed $10 million.

IRS Online Account

You can also schedule estimated payments through your IRS Online Account, which keeps your payment history and balance in one place.¹⁰

EFTPS

The Electronic Federal Tax Payment System still works for existing individual users, but the IRS no longer accepts new individual enrollments.¹¹ New filers should use Direct Pay or the Online Account.

Credit or Debit Card

Authorized third-party processors accept card payments and charge a convenience fee — a percentage for credit cards, typically a flat fee for debit cards. The fee is not deductible.

Mail

Detach the voucher for the quarter you’re paying and mail it with a check or money order made out to “United States Treasury.” Write your SSN, phone number, the tax year, and “Form 1040-ES” on the check. The mailing address depends on your state and is listed in the 1040-ES instructions. Your envelope must be postmarked on or before the due date.

Applying Last Year’s Overpayment

If you overpaid on your 2025 return, you can apply some or all of that overpayment to your 2026 estimated tax rather than taking a refund. You make the election on the 2025 return itself, and the amount credits to your first quarter. Once elected, the choice is one-way — you can’t later reverse it and ask for a refund of that amount. Track how much you applied and include it as part of your first quarter payment on the 1040-ES worksheet so you don’t pay it a second time.

If You Underpay

Falling short of the required minimum triggers an underpayment penalty, which functions as interest on the shortfall for each quarter it goes unpaid. The rate is 7% for the first quarter of 2026 and 6% for the second quarter; the IRS resets it every three months.¹² Because the penalty runs per quarter, you can still owe it for a specific period even if you overpaid on the year overall. Meeting either the 90%-of-current-year or 100%-of-prior-year (110% if higher income) threshold avoids it entirely.¹³

The IRS can waive the penalty in narrow situations. Federally declared disasters are usually handled automatically. For other casualties or unusual circumstances, or if you retired after age 62 or became disabled during the tax year or the year before, you can request a waiver by checking the appropriate box in Part I of Form 2210 and attaching an explanation with supporting documentation.¹⁴³ The waiver isn’t automatic; the IRS decides case by case.

If You Farm or Fish

Different rules apply if at least two-thirds of your 2025 or 2026 gross income comes from farming or fishing. You can make a single payment by January 15, 2027 instead of four installments, or skip estimated payments entirely if you file your 2026 return and pay in full by March 1, 2027.¹⁵ The 110% safe harbor does not apply to qualifying farmers and fishermen, and penalty calculations use Form 2210-F rather than the standard Form 2210.¹

State Taxes Are Separate

Form 1040-ES covers only your federal obligation. Most states with an income tax have their own estimated tax forms, thresholds (often lower than the federal $1,000), and due dates. Check your state’s department of revenue for its own vouchers and schedule. States without an individual income tax don’t require estimated payments.

1
Internal Revenue Service. Form 1040-ES – Estimated Tax for Individuals
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Internal Revenue Service. Estimated Taxes
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Office of the Law Revision Counsel. 26 USC 6654 – Failure by Individual to Pay Estimated Income Tax
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Internal Revenue Service. Topic No. 554 Self-Employment Tax
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Social Security Administration. What Is the Current Maximum Amount of Taxable Earnings for Social Security
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Internal Revenue Service. Instructions for Form 2210
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Internal Revenue Service. Individuals – When Are Quarterly Estimated Tax Payments Due
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Internal Revenue Service. Publication 509 (2026), Tax Calendars
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Internal Revenue Service. Direct Pay With Bank Account
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Internal Revenue Service. Payments
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Internal Revenue Service. EFTPS – The Electronic Federal Tax Payment System
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Internal Revenue Service. Quarterly Interest Rates
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Internal Revenue Service. Topic No. 306 – Penalty for Underpayment of Estimated Tax
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Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty
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Internal Revenue Service. Farming and Fishing Income