8878

IRS e-file Signature Authorization for Form 4868 or Form 2350

Agency
IRS
Revision
2025
Fillable fields
19
Pages
2
Official source
IRS form page
Checked
October 21, 2026
Fill 8878 online
Page 1 of form 8878

Form 8878: IRS e-file Signature Authorization for Form 4868 or Form 2350

Form 8878 is the IRS e-file Signature Authorization for Form 4868 or Form 2350, the two extension of time to file applications. This is the 2025 form, for the tax year ending December 31, 2025. The IRS About page says it is completed when Form 4868 is filed using the Practitioner PIN method, or when the taxpayer authorizes the electronic return originator (ERO) to enter or generate the taxpayer's personal identification number (PIN) on Form 4868 or Form 2350.

The ERO prepares the form, the taxpayer reviews and signs it, and the ERO keeps it. The form says "ERO must obtain and retain completed Form 8878" and "Don't Submit This Form to the IRS Unless Requested To Do So." The instructions add that Form 8878 is not itself an application for an extension of time to file.

The instructions are printed on page 2 of the same PDF. You can fill out Form 8878 free in your browser on this page and download it without an account.

Top of page 1 of Form 8878: IRS e-file Signature Authorization for Form 4868 or Form 2350, as printed by IRS

What's on Form 8878

Header

Submission Identification Number (SID), the taxpayer's name and social security number, and the spouse's name and social security number.

Part I: Information From Extension Form

Whole dollars only, one box checked: line 1 for Form 4868 with the amount paid from its line 7, or lines 2a and 2b for Form 2350 with the requested date and the amount paid from its line 5.

Part II: Taxpayer Declaration

A declaration under penalties of perjury, consent for the ERO or transmitter to send the form, and an electronic funds withdrawal authorization if it applies.

Part II: taxpayer and spouse PIN

For each person, a box to authorize the named ERO firm to enter or generate a five-digit PIN, or a box to enter the PIN personally, plus a signature and date.

Part III: Practitioner PIN Method for Form 4868 Only

The ERO's six-digit EFIN followed by a five-digit self-selected PIN, a certification, and the ERO's signature and date.

How Form 8878 is completed

  1. 1

    ERO: header and Part I

    The instructions say the ERO enters the taxpayer names and SSNs at the top and completes Part I with the required information from the selected extension form.

  2. 2

    ERO: PIN and firm name

    If authorized, the ERO enters or generates the taxpayer's PIN in Part II and writes the ERO firm name, not the individual preparer's name, on the authorization line.

  3. 3

    Taxpayer: review and sign

    The taxpayer verifies the extension application, checks one box, confirms a PIN of five digits other than all zeros, and signs by handwritten signature or by electronic signature if the software supports it.

  4. 4

    Taxpayer: return it to the ERO

    The instructions list hand delivery, U.S. mail, private delivery service, email, Internet website or fax. The application is not transmitted until the ERO receives the signed Form 8878.

  5. 5

    ERO: Part III if used

    Part III is completed only when Form 4868 is filed using the Practitioner PIN method. The instructions say the ERO may sign with a rubber stamp, mechanical device or computer software program.

  6. 6

    ERO: SID after filing

    The ERO enters the 20-digit Submission Identification Number assigned to the extension form, or associates Form 9325 with Form 8878 after filing.

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Where it goes and who keeps it

Not sent to the IRS

The form says "Don't Submit This Form to the IRS Unless Requested To Do So." The form also says "ERO Must Retain This Form."

Retention by the ERO

The instructions say the ERO keeps the completed Form 8878 for 3 years from the return due date or IRS received date, whichever is later. It may be kept electronically under Rev. Proc. 97-22.

Timing

The instructions say the ERO receives the completed and signed Form 8878 before the extension application is transmitted or released for transmission.

Copies for the taxpayer

The ERO gives the taxpayer a copy of the signed form on request, and a corrected copy if the extension form changes, for example after the taxpayer's review.

Cancelling a payment

The declaration says a payment is revoked by contacting the U.S. Treasury Financial Agent at 888-353-4537 no later than 2 business days prior to the payment (settlement) date.

Related forms

Who completes Form 8878?

  • Electronic return originators (EROs)

    The ERO enters the names and SSNs, completes Part I from the extension form, enters the ERO firm name when authorized, gives the form to the taxpayer and keeps the signed copy.

  • Taxpayers e-filing an extension through an ERO

    The taxpayer verifies the prepared extension application, checks a box in Part II, indicates or verifies the PIN, signs and dates the form, and returns it to the ERO.

  • Spouses on a joint application

    The spouse has a separate PIN section. The instructions say one spouse may authorize the ERO to enter their PIN while the other enters their own, but not the PIN of an absent spouse.

  • When it is not completed

    The chart in the instructions says not to complete it for a Form 4868 with no electronic funds withdrawal, or one where the taxpayer enters their own PIN and the ERO is not using the Practitioner PIN method.

The form is shared between an electronic return originator and the taxpayer. It is a record the ERO keeps, not a form a taxpayer sends to the IRS.

Official sources and the blank

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Questions about Form 8878

Is Form 8878 an extension request?

No. The instructions say Form 8878 is not an application for an extension of time to file. The extension is requested on Form 4868 or Form 2350.

Does the taxpayer send Form 8878 to the IRS?

No. The taxpayer returns it to the ERO, and the form says not to submit it to the IRS unless requested. The ERO keeps it for 3 years.

When is Form 8878 needed?

The About page says when Form 4868 is filed using the Practitioner PIN method, or when the taxpayer authorizes the ERO to enter or generate the taxpayer's PIN on Form 4868 or Form 2350.

What PIN can be used?

The form asks for five digits and says not to enter all zeros. The taxpayer either authorizes the ERO firm to enter or generate it, or enters it personally under the Practitioner PIN method.

What is Part III for?

Part III is the ERO's certification for the Practitioner PIN method, for Form 4868 only. The ERO enters a six-digit EFIN followed by a five-digit self-selected PIN and signs.

Can one spouse enter the other spouse's PIN?

The instructions say it is not acceptable for a taxpayer to select or enter the PIN of an absent spouse. One spouse may authorize the ERO while the other enters their own PIN.