FaxTerra
Complete Guide — Updated 2026

How to Fax the IRS

Which forms the IRS accepts by fax, all fax numbers organized by form, step-by-step sending instructions, and mistakes to avoid.

The IRS still relies heavily on fax. Dozens of forms have dedicated fax lines — in many cases, faxing is faster than mailing and produces a delivery confirmation that mail does not. In some cases, like Form 8806, fax is the only submission method the IRS accepts.

This guide covers every IRS form that can be faxed, the correct fax number for each, how long processing takes, and how to avoid the most common mistakes that cause submissions to be rejected or lost.

IRS Forms You Can Fax

These forms have official IRS fax numbers. Click any form for detailed instructions and state-specific fax numbers.

FormName
SS-4EIN ApplicationGuide
2553S-Corp ElectionGuide
2848Power of AttorneyGuide
8821Tax Info AuthorizationGuide
4506-TTranscript RequestGuide
5472Foreign-Owned EntityGuide
8802Residency CertificationGuide
8809Info Return ExtensionGuide
8806Acquisition of ControlGuide
911Taxpayer AdvocateGuide

Forms the IRS Does Not Accept by Fax

These are the most common forms people try to fax — and the IRS will not process them. If you’re looking to fax a personal tax return, the short answer is: you can’t. See individual form guides for your submission options.

1040 / 1040-SRMust be e-filed or mailed
1040-X (Amended Return)Mail or e-file only; IRS does not accept amended returns by fax
4868 (Extension)E-file or mail; no fax number published
W-4 (Withholding)Submit to your employer, not the IRS
1099s / W-2s (filing)File through FIRE system or mail; use Form 8809 to extend deadline
941 (Payroll)E-file or mail only
1065 / 1120 / 1120-SPartnership and corporate returns must be e-filed or mailed

Not sure which forms you can fax? See our guide: Can I fax my tax return to the IRS?

How to Fax a Form to the IRS

Follow these steps exactly to avoid the most common rejection reasons. New to online faxing? Our step-by-step guide to sending a fax walks through what you can send and how pages are counted.

1

Confirm you have the right form and the right version

The IRS publishes form updates annually. Using an outdated version of a form (especially Form 2848, 8821, or 2553) is one of the most common reasons for rejection. Download the current version from irs.gov before faxing.

2

Look up the correct IRS fax number for your state

Many IRS forms have different fax numbers depending on your state. Form SS-4, 2553, 2848, 8821, and 4506-T all have regional numbers. Using the wrong number sends your form to the wrong processing center — the IRS will not forward it. Use the form-specific guides above or the complete directory at /fax/irs-fax-numbers.

3

Complete every required field, especially signatures

Missing signatures are the top rejection reason for Forms 2848 and 8821. Missing CAF numbers, incomplete addresses, and undated signatures are also common triggers. Review the IRS instructions for your specific form before faxing.

4

Start from a clean, legible PDF or photo

Save the document as a clear PDF, or take a sharp, well-lit photo of each page. Faint or blurry source documents can render taxpayer identification numbers, dates, or signatures illegible at the IRS receiving end. FaxTerra transmits every fax at high resolution automatically — there is no resolution setting to choose.

5

Send and save your delivery confirmation

Your fax service will provide a delivery confirmation showing that the IRS line received the transmission. Save this confirmation. It is your proof that you submitted on time — critical if there is a deadline involved (Form 2553, 8806, 8809) or a dispute about whether a form was filed.

6

Follow up if you expect a response

The IRS does not send fax confirmations automatically. If your form should generate a response (EIN by fax for SS-4, CP 261 for Form 2553), wait the stated processing window before calling the IRS. If you need to receive IRS faxes, you need a dedicated fax number — see our guide on receiving faxes from the IRS.

Common Mistakes That Get Faxes Rejected

The IRS processes millions of faxed forms per year. These are the most frequent reasons they are returned or ignored:

Wrong fax number for your state
Form 2553, 2848, 8821, and 4506-T each have multiple numbers. Sending to the wrong regional center causes delays of weeks or months.
Missing or undated signature
The IRS will reject Form 2848 if signed before it was dated, or if the date is missing. Form 8821 has the same requirement.
Outdated form version
The IRS updates forms regularly. An outdated revision will be returned. Always download from irs.gov.
Incomplete CAF number on Power of Attorney
Forms 2848 and 8821 require a Centralized Authorization File (CAF) number for the appointee. If the number is missing or wrong, the form is returned with Letter 861C.
Faxing a form that must be mailed or e-filed
The most common: trying to fax a 1040, 1040-X, or 941. These forms have no IRS fax number and will not be received by the right unit.
A blurry or faint source document
A dark, angled, or out-of-focus photo can make taxpayer ID numbers and small print unreadable at the receiving end. Start from a clean scan or a sharp, well-lit, straight-on photo — FaxTerra transmits at high resolution automatically.

Frequently Asked Questions

Does the IRS accept faxes?

Yes, but only for specific forms. The IRS accepts faxes for EIN applications (SS-4), power of attorney (Form 2848), S-corp elections (Form 2553), tax transcript requests (Form 4506-T), and several others. Standard tax returns (1040, 1065, 1120) cannot be faxed.

How long does it take the IRS to process a faxed form?

Processing times vary by form. For SS-4 EIN applications the IRS quotes 4 business days; the median we measure across real filings is about 2 weeks. S-corp elections (Form 2553) take about 60 days before you receive CP 261 confirmation. Power of attorney (Form 2848) and Form 8821 go through the IRS CAF unit, where processing time varies. Transcript requests (Form 4506-T) typically take a few weeks.

Will the IRS confirm it received my fax?

The IRS does not send automatic fax confirmations. Your fax service provides delivery confirmation — a record that the IRS fax line received the transmission. For EIN applications (SS-4), the IRS faxes your EIN back — it quotes 4 business days, though about 2 weeks is typical in practice, and the fax-back needs a number that can receive it. For S-corp elections, you'll receive CP 261 by mail in about 60 days. For most other forms, there is no confirmation unless the IRS has questions.

How do I make sure the IRS can read my faxed form?

Start from a clean, legible scan or a well-lit, straight-on photo — a sharp source document is what keeps small print like taxpayer identification numbers and signature blocks readable. FaxTerra transmits every fax at high resolution automatically, so there is no resolution setting to adjust before sending.

Can I fax an amended tax return (Form 1040-X) to the IRS?

No. The IRS does not accept Form 1040-X by fax. Amended returns must be mailed or, in some cases, e-filed. If you need faster processing, e-file the amendment through your tax software.

What happens if I fax to the wrong IRS number?

The fax will be received by the wrong IRS unit and may not reach the correct processing center. The IRS does not forward misdirected faxes — your form may be ignored or lost. Always verify the fax number on irs.gov before sending, and use form-specific guides to confirm which number applies to your state or situation.

Is faxing to the IRS secure?

Traditional fax lines are generally considered secure for tax purposes — the IRS has accepted fax for decades. Online fax services like FaxTerra use TLS 1.3 encryption in transit and AES-256 encryption at rest. Do not send tax documents through free consumer fax apps that do not disclose their security practices.

Can I get a fax number so the IRS can fax me back?

Yes. If you fax a form that may prompt an IRS response (like a rejected Form 2848 or a request for additional documentation), you need a dedicated fax number for the IRS to reach you. With a FaxTerra Starter subscription ($4.99/month), you get a dedicated fax number — you're notified by email and on your phone, and can view or download each incoming fax as a PDF from your inbox.

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