Corporate Estimated Tax Payments: Who Pays and When

Corporate estimated tax payments follow their own statute, IRC 6655, not the individual rules in section 6654. The threshold, the due dates, the safe harbor percentages and the penalty period are all different, and there is no January payment. This guide covers who pays, when, how much, the large corporation limit, the two methods for uneven income, EFTPS, what replaced Form 1120-W, the Form 2220 penalty and S corporations, with a calendar-year illustration. Owners paying on pass-through income should use the quarterly estimated taxes guide instead.

Who pays: corporations expecting $500 or more of tax

The 2025 Form 1120 instructions state the rule: a corporation must make installment payments of estimated tax if it expects its total tax for the year, less applicable credits, to be $500 or more. IRC 6655(f) mirrors it from the penalty side: no addition to tax when the tax shown on the return is less than $500. “Tax” under 6655(g)(1) is the section 11 income tax plus the corporate alternative minimum tax and the base erosion tax, less credits. At the 21% rate in IRC 11(b), $500 of tax corresponds to roughly $2,400 of taxable income, so nearly every profitable C corporation is inside the rule.

The four due dates, for calendar and fiscal years

The fourth installment lands inside the tax year, on December 15. Any balance is paid with Form 1120 by the 15th day of the 4th month after year end, April 15, 2027 for calendar 2026; the filing dates and the Form 7004 extension are in the C corp tax deadline guide, and every installment date with a download is on the business tax calendar.

How much: the required annual payment

Under IRC 6655(d)(1), each required installment is 25% of the “required annual payment,” which is the lesser of 100% of the tax shown on the return for the current year or 100% of the tax shown on the prior year's return. The prior-year option is not available if the preceding year was not a 12-month year or the prior return showed no tax liability. Publication 542 calls these Method 1 and Method 2 and tells corporations to use whichever gives the smaller installments. Unlike the individual safe harbor, there is no 90% option and no 110% tier: both measures are 100%.

Large corporations: last year's tax works only for the first installment

IRC 6655(g)(2) defines a large corporation as one that had taxable income of $1,000,000 or more in any of the three preceding tax years, ignoring net operating loss and capital loss carryovers and dividing the $1,000,000 among members of a controlled group. For a large corporation, 6655(d)(2) removes the prior-year option, with one exception: the first installment may still be based on last year's tax, and any reduction that produces is recaptured by adding it to the second installment. The Form 2220 instructions build that recapture into line 10, and require a large corporation using the prior-year first installment to attach Form 2220 even when no penalty is due.

Uneven income: the annualized income and adjusted seasonal methods

A corporation whose profit arrives late in the year can pay less early under IRC 6655(e). The annualized income installment annualizes taxable income for the first 3 months (for the first and second installments), 6 months (third) and 9 months (fourth), applies 25%, 50%, 75% and 100% of the resulting tax, and subtracts prior installments. The adjusted seasonal installment is available only when the base period percentage for any 6 consecutive months is at least 70%, and it follows the income pattern of the three prior years. Any reduction is recaptured in the next installment. Both are computed on Schedule A of Form 2220, and a corporation that uses either must attach Form 2220 to its return and check the box on Form 1120, line 34, even with no penalty.

How to pay: electronic funds transfer through EFTPS

Corporations must use electronic funds transfer for all federal tax deposits, including estimated income tax. The Form 1120 instructions name two free methods, EFTPS and the corporation's IRS business tax account, and allow a tax professional, bank or payroll service to make deposits on the corporation's behalf, or a same-day wire arranged with its bank. The IRS EFTPS page says new enrollments can take up to five business days, so a new corporation should enroll before its first installment date. Payments can be scheduled up to 365 days ahead.

Form 1120-W is historical; the worksheet lives in Publication 542

Form 1120-W, the old Estimated Tax for Corporations worksheet, is no longer revised. Publication 542 (Rev. January 2024) states that the form and its instructions “are now historical” and that the 2022 revisions were the last; the About Form 1120-W page on IRS.gov returned a page-not-found error when checked on September 26, 2026. The 2025 Form 1120 instructions send corporations to section 6655 and Publication 542, which carries an Estimated Tax Worksheet of its own: expected taxable income times the maximum rate, less credits, plus other taxes, less refundable credits (line 8, which ends the exercise if under $500), compared with the prior year's tax, with 25% of the smaller figure as each installment.

The underpayment penalty and Form 2220

IRC 6655(a) adds to the tax an amount figured by applying the section 6621 underpayment rate to each underpaid installment for the period from its due date until the earlier of payment or the 15th day of the 4th month after year end. The IRS sets the rate quarterly; its quarterly interest rates page shows 7% for the fourth quarter of 2026, and the 2025 Form 2220, Part IV, applies it day by day. The IRS corporate penalty page says the IRS cannot adjust this penalty for reasonable cause; it can be reduced only by showing the payments were made, by the under-$500 rule, or by the consolidated-group first-installment rule. Most corporations do not file Form 2220: the instructions say the IRS figures the penalty and sends a notice, and the form is required only for the annualized, seasonal and large-corporation situations above. The individual penalty is covered in the underpayment penalty guide.

S corporations: estimates only for entity-level taxes

An S corporation generally pays no income tax, so IRC 6655(g)(4) limits its estimated tax to three items treated as section 11 tax: the built-in gains tax (section 1374), the excess net passive income tax (section 1375) and investment credit recapture under section 1371(d)(2). The large corporation rule does not apply to it, the prior-year test is modified, and its penalty period ends at the 3rd month after year end rather than the 4th. Shareholders cover the tax on pass-through income through their own estimates or withholding, as the estimated tax safe harbor guide explains.

Illustration: a calendar-year corporation with $210,000 of 2026 tax

Sources: 26 U.S.C. 6655, failure by corporation to pay estimated income tax; 26 U.S.C. 11(b), 21% corporate rate; 26 U.S.C. 6654(d), the individual required annual payment, for contrast; IRS, 2025 Instructions for Form 1120 (Estimated Tax Payments; Electronic Deposit Requirement); IRS Publication 542 (Rev. January 2024), Corporations, including the Estimated Tax Worksheet; IRS Form 2220 (2025), Underpayment of Estimated Tax by Corporations; IRS, 2025 Instructions for Form 2220; IRS, Underpayment of Estimated Tax by Corporations penalty (reviewed November 4, 2025); IRS, EFTPS: The Electronic Federal Tax Payment System (reviewed June 28, 2026); IRS, Quarterly interest rates (2026). Rules, dates and rates checked against these sources on September 26, 2026. This is general information, not tax advice for your situation. Tax services are provided by licensed tax professionals under a separate engagement agreement. BEG does not provide tax advice.