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Entity guide

How to file a tax extension for an S corporation

S corporations file Form 7004 to get an automatic six-month extension of Form 1120-S. For calendar-year S corporations the 1120-S — and the Form 7004 that extends it — is due , and the extension moves the return to . An LLC with an S election uses the same form. We e-file it for a flat $9.95.

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Extending the 1120-S does not extend the shareholders' personal returns. Each shareholder's Form 1040 is still due unless they file their own Form 4868 — and their tax is due that day either way. See the penalties guide.

Who files Form 7004 for an S corporation?

Any corporation or LLC with an accepted S election files Form 7004 in the company's name, using its EIN (Employer Identification Number), to extend Form 1120-S. The 7004 identifies the return by a form code — 25 for Form 1120-S — which our wizard fills in for you. The extension is generally automatic when Form 7004 is timely and properly filed. No explanation of why additional time is needed is required, but the filer must make a proper estimate of tax when applicable and pay any tax due by the regular due date.

When is the S-corp extension deadline?

For calendar-year S corporations, Form 7004 is due — the same day Form 1120-S is due — and extends the return to . That is one month before the personal deadline, and owners who think of April as tax day routinely miss it. The rule is the 15th day of the 3rd month after the tax year ends; a fiscal-year S corporation counts from its own year-end and still gets six months, though S corporations generally must use a permitted tax year. A permitted year may be the calendar year, a natural business year, an ownership tax year, a year elected under section 444, a qualifying 52-53-week year, or another tax year for which the corporation establishes a business purpose.

All 2027 extension deadlines →Fiscal-year deadlines →

How do I file the S-corp extension?

  1. Choose the 1120-S return

    In the wizard, pick "S Corporation (Form 1120-S)" — we map it to the right Form 7004 code for you.

  2. Enter your details

    Legal company name, EIN, address, and tax year. Most S corporations owe no tax of their own — income passes through to the shareholders — so the tentative-tax (estimated tax) and balance-due fields are usually zero.

  3. Pay the fee

    $9.95, shown before you pay, with no hidden add-ons.

  4. We e-file with the IRS

    We transmit directly to the IRS and email you the moment your extension is accepted. Your EIN is encrypted at rest, never stored in your browser, and shown only masked after filing.

What about the shareholders' Schedule K-1s?

The extension delays the K-1s too: Schedules K-1 (Form 1120-S), the statements of each shareholder's share of the income, are due to shareholders by the date the 1120-S is due, including extensions, so extending to moves the K-1 deadline as well. Since a shareholder cannot finish their Form 1040 without the K-1, an extended S corporation usually means extended shareholders: each files Form 4868 by to move their 1040 to . Their tax is not extended — each shareholder who needs additional filing time should file Form 4868 by the applicable deadline and make a reasonable estimate of their total individual tax liability using the information reasonably available at that time, including available information from the S corporation.

Does the extension give us more time to pay?

No. Form 7004 extends the time to file Form 1120-S, not the time to pay any entity-level tax (tax the company itself owes), and it does nothing for the shareholders' personal tax. Interest (the federal short-term rate plus 3%, compounded daily) and the failure-to-pay penalty (0.5% per month, up to 25%) run from on unpaid entity-level tax; the shareholders' tax is due through estimated payments or with Form 4868. The payment guide explains how to estimate.

What happens if we miss the March deadline?

If Form 7004 is not filed by , you cannot extend, and the late-filing penalty starts the next day — per shareholder, per month or part of a month, for up to 12 months, even if the company owes no tax. For returns required to be filed in 2027, the late-filing penalty is $260 per shareholder for each month or part of a month the return is late, for up to 12 months. A three-shareholder S corporation filing two months late could therefore face a $1,560 penalty. Separate penalties may apply to unpaid entity-level tax, including the failure-to-pay penalty when applicable. The per-shareholder late-filing penalty under §6699 applies to the late Form 1120-S itself. File the 1120-S as soon as possible — the clock stops when it is filed. If a penalty is assessed, the corporation may request reasonable-cause relief when the facts support it. For eligible original Forms 1120-S due on or after January 1, 2027, a qualifying S corporation with the required history of timely filing and payment may receive relief from the §6699 penalty automatically under the IRS's Automatic Exemption from Penalty (AEP) program. In practice: file the 1120-S now; if a penalty notice follows, check whether AEP already applied before requesting reasonable-cause relief. See what to do if you missed the extension deadline.

How much does an S-corp extension cost?

We e-file Form 7004 for a flat $9.95; the IRS charges nothing for the extension itself (see pricing). Shareholders who need their own Form 4868 can file it free through IRS Free File. If the IRS rejects the extension and we cannot get it accepted, we refund the fee. More in the cost guide.

Rare cases

Most S corporations can skip these. Open one only if it applies to you.

Does the S corporation itself owe tax with the extension?

Usually not — an S corporation passes its income through to its shareholders — but a few entity-level taxes are paid with Form 1120-S, and those are still due by even when you extend.

  • Built-in gains tax (section 1374): a company that converted from a C corporation and sells assets that had appreciated at the time of conversion, within the five-year recognition period.
  • Excess net passive income tax (section 1375): an S corporation that still holds accumulated earnings and profits from its C-corporation years and whose passive investment income exceeds 25% of gross receipts. If the corporation has accumulated earnings and profits at the close of each of three consecutive tax years and more than 25% of gross receipts in each of those years is passive investment income, the S election terminates on the first day of the following tax year.
  • LIFO recapture tax (section 1363(d)): if a C corporation used the LIFO inventory method before its S election becomes effective, the LIFO recapture amount is included in income for its final C-corporation year. The resulting additional tax is generally paid in four equal installments: the first with the final C-corporation return and the remaining three by the due dates of the next three Form 1120-S returns.

If an entity-level tax is due with Form 1120-S, include the applicable tentative tax and payments on Form 7004 and pay the amount due by the regular due date. For LIFO recapture, only the installment due for the current S-corporation year belongs with that year's Form 1120-S liability; the first installment was due with the final C-corporation return. Otherwise the tax lines on the 7004 are simply zero.

We filed our S election late — does that change the deadline?

No. A late Form 2553, or a request for late-election relief, does not change when Form 1120-S is due: it is still the 15th day of the 3rd month after year-end, with the Form 7004 due the same day. If the S election is pending at the extension deadline, the extension strategy should be based on the return the taxpayer reasonably expects to file and the status of any late-election relief request. If the S election is ultimately not accepted, a different return may be required and a Form 7004 filed for Form 1120-S may not protect the filing deadline for that different return. If the corporation qualifies for Rev. Proc. 2013-30 relief, Form 2553 may be attached to the initial Form 1120-S in certain circumstances. The Form 2553 must be marked “FILED PURSUANT TO REV. PROC. 2013-30” and the Form 1120-S must be marked “INCLUDES LATE ELECTION(S) FILED PURSUANT TO REV. PROC. 2013-30.” The corporation must also satisfy the eligibility, timing, reasonable cause, and consistent filing requirements of the revenue procedures. If the S election is ultimately not effective, the entity generally must file the return required under its underlying federal tax classification; consult your tax professional.

S-corp extension FAQ

What form does an S corporation use to file a tax extension?

Form 7004, the Application for Automatic Extension of Time To File Certain Business Income Tax, Information, and Other Returns. It extends Form 1120-S by six months. An LLC taxed as an S corporation uses the same form.

When is Form 1120-S due in the 2027 season?

March 15, 2027 for calendar-year S corporations, with an extension to September 15, 2027 if Form 7004 is filed by the original date. Fiscal-year S corporations are due on the 15th day of the 3rd month after their year-end.

Does the 1120-S extension extend the shareholders' personal returns?

No. Form 7004 extends only the company's return. Each shareholder who needs more time files their own Form 4868 by April 15, 2027, and their personal tax is still due on that date.

Do we still have to send K-1s by the original date if we extend?

No. Schedules K-1 are due when the return is due, including extensions, so extending the 1120-S also extends the K-1s. Shareholders waiting on a K-1 usually file their own Form 4868 and pay an estimate of their share.

Is there a penalty for filing Form 1120-S late if we owe no tax?

Yes. The late-filing penalty is charged per shareholder, per month or part of a month, for up to 12 months, and the amount is indexed each year. It applies whether or not the company owes any tax.

Does Form 7004 extend the time to pay built-in gains tax?

No. Built-in gains tax, excess net passive income tax, and any other entity-level tax are due by the original due date (March 15, 2027 for calendar-year filers). Report the tentative tax on the 7004 and pay it with the extension.

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