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Official form guide
Form 8879C: IRS e-file Signature Authorization for Form 1120
IRS Form 8879-C is an e‑file signature authorization for Form 1120 that lets a corporate officer use a five‑digit PIN to sign the corporation’s 2021 electronic income tax return. The form must be retained for 3 years from the return due date.
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IRS Form 8879C - IRS e-file Signature Authorization for Form 1120
IRS Form 8879-C is an e‑file signature authorization for Form 1120 that lets a corporate officer use a five‑digit PIN to sign the corporation’s 2021 electronic income tax return. The form must be retained for 3 years from the return due date.
Risk Radar
Scan points- 1Submitting the form without the officer’s signed PIN blocks the e‑file transmission.
- 2Officer’s signature missing from Part II, preventing transmission of the return.
- 3Entering all zeros as the officer’s PIN, which is prohibited by the form instructions.
- 4Failing to check the correct authorization box in Part II for PIN entry.
- 5Omitting the corporation’s name or employer identification number at the top of the form.
Plain English
This form lets a corporation’s officer approve an electronic filing of its 2021 tax return by using a personal PIN. The officer signs the form and the electronic return originator keeps it on file.
Submission Date
- Filing date: 2021-11-16 22:14:01
- Preparation window: collect IDs, supporting records, and signatures in advance.
- Final review: verify names, dates, and required fields before submission.
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What this form is for
- Use this form when the corporate officer wants to use a personal identification number (PIN) to electronically sign the corporation’s 2021 electronic income tax return and, if applicable, consent to electronic funds withdrawal.
- Do not use it when the corporate officer is not using a PIN to sign the return.
- Check Form 8453-C instead when the corporate officer is not using a PIN to sign the return.
Form selector
Use this form or another form?
Officer wants to sign electronically using a PIN
Provides PIN authorization for the 2021 corporate return
✓ Confirm the officer’s five‑digit PIN is not all zeros
Officer does not want to use a PIN
Required when no PIN authorization is used for the corporate return
✓ Verify the officer will sign the paper declaration instead
Filing the corporation’s 2021 income tax return
The return that the PIN authorizes
✓ Ensure the return’s line amounts match Part I entries
Deadline or filing window
Not stated in the official source.
Checklist
What you need before filling it out
Officer’s PIN (Part II)
Five‑digit PIN not all zeros · Officer provides PIN
Officer’s signature (Part II)
Officer’s handwritten signature · Part II signature line
EFIN and PIN (Part III)
Six‑digit EFIN and five‑digit PIN · Part III certification
Total income (Part I)
Whole‑dollar amount from Form 1120 line 11 · Part I field 1
Retention period
Record‑keeping policy · Instructions page
Before you submit
- 1Obtain the corporation’s 2021 Form 1120 and verify line amounts.
- 2Enter the corporation’s name and EIN at the top of Form 8879‑C.
- 3Fill Part I with the total income, taxable income, total tax, amount owed, and overpayment from the return.
- 4In Part II, check the box to authorize the ERO to enter the PIN or choose to enter it personally.
- 5Enter the five‑digit PIN (not all zeros) in the appropriate field.
- 6Officer signs, dates, and prints title in Part II.
- 7ERO completes Part III with the six‑digit EFIN and the officer’s PIN, then signs and dates.
- 8Retain the completed Form 8879‑C for three years.
- 9Transmit the electronic return only after the ERO has received the signed Form 8879‑C.
How to file this form
- 1Enter the corporation’s name and EIN on the top of Form 8879‑C.
- 2Populate Part I with the dollar amounts from the corporation’s 2021 Form 1120.
- 3Officer selects the authorization option in Part II and provides a five‑digit PIN.
- 4Officer signs, dates, and prints title on Part II.
- 5ERO completes Part III with the six‑digit EFIN and the officer’s PIN, then signs and dates.
- 6ERO retains the signed Form 8879‑C as proof of authorization for three years.
Known limitations
- 1Only applicable to a corporation’s 2021 electronic income tax return (Form 1120).
- 2Does not apply when the corporate officer chooses not to use a PIN; Form 8453‑C must be used instead.
- 3The form must not be mailed to the IRS; it is retained by the ERO.
Field map
Compact field-by-field guide
Entity Info
1 items
Name and taxpayer ID of the entity claiming the credit.
Credit Info
1 items
Type of credit or incentive being claimed.
Calculation
2 items
The base amount used to calculate the credit.
Calculated credit amount after applying formulas and limitations.
Certification
1 items
Detailed breakdown supporting the credit calculation.
Signatures
1 items
Sign and date the form.
Almost done reviewing the fields?
Fillable formOpen in Editor->The form is the 2020‑2021 edition (revision 20 21) and the PDF directs users to www.irs.gov/Form8879C for the latest information; no specific changes are listed in the source.
What changed or needs a fresh check
- Edition date — confirm the form shows the 20 21 revision
- Fee — Not stated in the official source
- Mailing address — Not stated in the official source
- Signature — confirm officer’s signature, date, and title are entered in Part II
- PIN format — confirm the PIN is five digits and not all zeros
Quick Facts
Downloads
After you file
- 1Store the signed Form 8879‑C in the corporation’s records for three years from the return due date or IRS receipt date, whichever is later.
- 2If requested, provide the officer with a copy of the signed form.
- 3If any return data changes, issue a corrected Form 8879‑C to the officer.
- 4Maintain electronic backup in compliance with Rev. Proc. 97‑22.
- 5Monitor for any IRS request to submit the form; otherwise keep it on file.
Sources
- SRCForm p.1 — title and edition: “Form 8879‑C 20 21 IRS e‑file Signature Authorization for Form 1120”.
- SRCForm p.2 — purpose: “A corporate officer and an electronic return originator (ERO) use Form 8879‑C when the corporate officer wants to use a personal identification number (PIN) to electronically sign a corporation’s electronic income tax return”.
- SRCForm p.2 — alternative form: “A corporate officer who does not use Form 8879‑C must use Form 8453‑C”.
- SRCForm p.2 — retention: “Retain the completed Form 8879‑C for 3 years from the return due date or IRS received date, whichever is later”.
- SRCForm p.2 — PIN rules: “The PIN must be five digits other than all zeros”.
- SRCForm p.2 — delivery methods: “Acceptable delivery methods include hand delivery, U.S. mail, private delivery service, email, Internet website, and fax”.
- SRCForm p.2 — ERO responsibilities: “Enter the name and employer identification number of the corporation at the top of the form”.
- SRCForm p.2 — officer responsibilities: “Officer signs, date, and enter his or her title in Part II”.
- SRCForm p.1 — “Do not send to the IRS” notice.
- SRCForm p.1 — “Go to www.irs.gov/Form8879C for the latest information”.
Common confusion points
Can I send Form 8879‑C to the IRS?
The form says “Do not send to the IRS.”
→ Verify the form’s top instruction that it is retained by the ERO.
Do I need to enter all zeros for my PIN?
Instruction prohibits all‑zero PIN.
→ Ensure the PIN entered is five digits and not all zeros.
Is the form only for 2021 returns?
The form is labeled 2020‑2021 and references the 2021 tax year.
→ Confirm the tax year on the form matches the return year.
Do I need a separate signature from the ERO?
Part III requires the ERO’s signature and EFIN.
→ Check that the ERO has signed and dated Part III.
Can I use the form for a paper‑filed return?
The form is for electronic filing only.
→ Verify the return will be e‑filed.
What if the officer wants to enter the PIN themselves?
Part II offers a box to not authorize the ERO.
→ Confirm the officer selected the correct box and entered the PIN personally.
Workflow map
Related forms and next steps
Before
Current
After
Often used with
⚠ If something goes wrong
- Form 8879-C — the officer can provide a corrected copy to the ERO.
Questions about IRS Form 8879C
What is IRS Form 8879C used for?
This form lets a corporation’s officer approve an electronic filing of its 2021 tax return by using a personal PIN. The officer signs the form and the electronic return originator keeps it on file.
Who must file IRS Form 8879C?
A corporate officer of the corporation, together with the electronic return originator (ERO), must complete and sign Form 8879‑C.
What information does IRS Form 8879C require?
Part I records the corporation’s total income, taxable income, total tax, amount owed and overpayment from the 2021 return. Part II captures the officer’s PIN, signature, date and title, while Part III contains the ERO’s certification and EFIN/PIN.
Where do I file IRS Form 8879C?
Do not send Form 8879‑C to the IRS; the electronic return originator retains the completed form and must keep it for 3 years from the return due date or IRS receipt date, whichever is later.
How do I complete IRS Form 8879C?
The ERO enters the corporation’s name and EIN and copies the amounts from the 2021 return into Part I. The officer reviews the return, selects the appropriate box in Part II, provides a five‑digit PIN (not all zeros), signs, dates and titles the form, then returns it to the ERO. The ERO completes Part III with a signature, date, and the six‑digit EFIN followed by the officer’s PIN, and retains the form.
What happens if IRS Form 8879C is filed incorrectly?
If the officer’s signed PIN is not received, the corporation’s return cannot be transmitted to the IRS, and the officer’s declaration is made under penalties of perjury.
Can I send Form 8879‑C to the IRS?
The form says “Do not send to the IRS.” Verify the form’s top instruction that it is retained by the ERO.
Do I need to enter all zeros for my PIN?
Instruction prohibits all‑zero PIN. Ensure the PIN entered is five digits and not all zeros.
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