Fillable Form 8879-C – Electronic Signature for Corporate Tax Returns

Form 8879-C is the IRS’s official authorization form that lets a corporate officer use a Personal Identification Number (PIN) to electronically sign a corporation’s income‑tax return. It’s required when you want to e‑file a corporate return (Form 1120, 1120‑S, etc.) and, if applicable, consent to electronic funds withdrawal.

What Is Form 8879-C?

This fillable PDF serves as the electronic signature agreement between the corporate officer and the Electronic Return Originator (ERO). By completing Form 8879-C you confirm that the information on the tax return is accurate and that you authorize the IRS to accept the electronic filing.

Key Fields & How to Complete the Form

When you open the form, focus on these sections:

• Corporation’s name and EIN – Must match the return.
• Officer’s name, title, and signature PIN – The PIN is your secure electronic signature.
• ERO’s name and PTIN – Filled by the tax preparer.
• Consent to electronic funds withdrawal – Check if you want the IRS to pull any balance due.

All fields are interactive in the fillable PDF, and Formize’s online filler will guide you through each step.

Common Mistakes to Avoid

• Entering an incorrect EIN – the IRS will reject the filing.
• Using a PIN that has been previously assigned to another corporation.
• Leaving the “Consent to electronic funds withdrawal” box unchecked when a payment is due.
• Signing the PDF in a desktop editor and then re‑uploading – this can corrupt the fillable fields.

How to Submit Your Signed Form

After you finish the Form 8879‑C in Formize, click the **Submit** button. The signed PDF is securely transmitted to the ERO, who attaches it to the corporate return and completes the e‑file.

Why Use Formize’s Online PDF Filler?

Formize loads the official IRS fillable PDF directly in your browser, so you never need to download, install, or edit the file manually. Your data stays encrypted, and the app automatically validates required fields before you submit.