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Tax Extension Deadlines Tracker: 1040, 1065, 1120-S, 1120 | HelloBooks Original and extended due dates for calendar-year 1040, 1065, 1120-S and 1120 returns for tax years 2025 and 2026, with the extension form for each.

Tracker · Extensions

Extension deadline tracker

Pick a return type and tax year to see the original due date, the extended date and which form gets the extension. Below the tool is the full table for every return type.

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Original due date
Thursday, April 15, 2027
Extension form
Form 4868
Extended due date
Friday, October 15, 2027

From the IRS draft of Publication 509 (2027). Tax is still due by the original date.

Every return type at a glance

ReturnTax yearOriginal due dateExtend withExtended due date
Form 10402025April 15, 2026Form 4868October 15, 2026
Form 10652025March 16, 2026Form 7004September 15, 2026
Form 1120-S2025March 16, 2026Form 7004September 15, 2026
Form 11202025April 15, 2026Form 7004October 15, 2026
Form 10402026 (draft dates)April 15, 2027Form 4868October 15, 2027
Form 10652026 (draft dates)March 15, 2027Form 7004September 15, 2027
Form 1120-S2026 (draft dates)March 15, 2027Form 7004September 15, 2027
Form 11202026 (draft dates)April 15, 2027Form 7004October 15, 2027

An extension to file is not an extension to pay

Form 4868 and Form 7004 give six more months to file. Tax still has to be paid by the original date, so send each extended client an estimate of the balance due with the extension notice.

Running the extension list

  • Decide on extensions a week before the original date, not the night before.
  • Record the extension acceptance for each return.
  • Move extended returns into a second production queue with its own internal cutoff.
  • Tell clients the new date in writing and what you still need from them.
FAQ

Frequently asked questions

Does the tracker cover fiscal-year entities?
No. It shows calendar-year filers. A fiscal-year return is due on the same month-based rule counted from its year end.
Why are some 2027 dates marked draft?
Tax year 2026 deadlines come from the IRS draft of the 2027 Publication 509 until the final version is released.
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One page per 2025 and 2026 federal change

Sources

Federal dates for calendar-year filers from IRS Publication 509. Check for disaster postponements and state dates before relying on them.

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