To fax documents to the IRS, use the fax number printed on the notice or letter the agency sent you, include a cover sheet with your name, taxpayer identification number, and the notice number, sign any forms in ink, and save the transmission confirmation report as your proof of delivery. Faxing works for responses to IRS notices, authorization forms, and documents requested during an examination. It does not work for filing a tax return.
What You Can and Can’t Fax
The IRS will not process a faxed Form 1040 or other tax return. Faxing is reserved for supporting documents and specific forms, almost always in response to something the IRS sent you first.
The situations where faxing is accepted include:
- Responding to a CP2000 notice, which the IRS sends when reported income doesn’t match what employers or banks reported. You have 30 days to respond (60 if you live outside the United States), and fax is one of the accepted methods. A CP2000 is not an audit; it’s an automated matching notice.1Internal Revenue Service. Topic No. 652, Notice of Underreported Income – CP20002Internal Revenue Service. IRS Letter CP2000 Proposed Changes to Your Tax Return
- Sending receipts, bank statements, or other records to a revenue agent conducting an examination.
- Submitting Form 14039 (Identity Theft Affidavit). The IRS now lists online submission as the preferred method, but the general fax number is 855-807-5720. If your notice lists a different number, use that one.3Internal Revenue Service. Form 14039 Identity Theft Affidavit
- Filing Form 2848 (Power of Attorney) or Form 8821 (Tax Information Authorization) with the Centralized Authorization File (CAF) unit.4Internal Revenue Service. The Centralized Authorization File (CAF) – Authorization Rules
- Requesting help through Form 911 (Taxpayer Advocate Service), which goes to 855-828-2723, or 304-707-9793 from outside the U.S.5Internal Revenue Service. Request for Taxpayer Advocate Service Assistance
The rule of thumb: if the IRS gave you a fax number on the notice, you can fax. If no fax number appears, mail or the IRS Document Upload Tool are your options.
Finding the Right Fax Number
The IRS runs dozens of specialized units across multiple processing campuses, and each has its own fax number. Sending to the wrong one can delay your case by weeks. The most reliable source is the notice itself, where the fax number is usually printed on the top left of the first page.6Internal Revenue Service. Understanding Your CP2000 Series Notice
CP2000 Notices
Each CP2000 lists a fax number tied to the campus handling your case. Match the number to the location on your notice, not the one geographically closest to you:
- Andover, MA: 877-477-9485
- Atlanta, GA: 877-477-0967
- Austin, TX: 877-477-0583
- Holtsville, NY: 877-477-9599
- Fresno, CA: 877-477-0962
- Ogden, UT: 877-477-9640
- Philadelphia, PA: 877-477-9602
Forms 2848 and 8821
Power of attorney and tax information authorization forms go to the CAF unit for your region. Generally, states east of the Mississippi go to Memphis and states west go to Ogden, with a few exceptions.4Internal Revenue Service. The Centralized Authorization File (CAF) – Authorization Rules
- Memphis (eastern states): 855-214-7519
- Ogden (western states): 855-214-7522
- International (APO/FPO, territories, foreign addresses): 855-772-3156, or 304-707-9785 from outside the U.S.
These numbers can change. Check the current Form 2848 instructions on IRS.gov before sending.7Internal Revenue Service. Instructions for Form 2848
International Accounts
Taxpayers abroad with questions about international tax accounts can fax the International Taxpayer Service Center at 681-247-3101 (international tax account issues only). The Taxpayer Advocate Service line for overseas taxpayers is 304-707-9793.8Internal Revenue Service. Contact My Local Office Internationally
What to Put on the Cover Sheet
Every fax to the IRS needs a cover sheet. Without routing information at the top, documents sit in a queue or attach to the wrong account. Include:
- Your full legal name and Social Security Number (or ITIN if you don’t have an SSN). This is what links your documents to the right account.
- The notice or letter number, printed on the right corner of the IRS letter, usually starting with CP or LTR.9Internal Revenue Service. Understanding Your IRS Notice or Letter
- The tax year the response relates to. Include it even if you think it’s obvious, particularly if you have issues open for more than one year.
- The total page count. “Page 1 of 12” format works, or at minimum state the total on the cover sheet so the receiving agent can confirm nothing dropped.
- A daytime phone number, in case pages come through illegibly or the agent needs to clarify something.
For Form 14039, the IRS specifically asks that you mark the cover sheet “Confidential.”3Internal Revenue Service. Form 14039 Identity Theft Affidavit
Signatures Must Be in Ink
This trips people up. The IRS does not accept electronic or typed signatures on forms submitted by fax. If you’re faxing Form 2848, Form 8821, or any other form that requires a signature, you have to sign it by hand in ink first, then scan or feed the signed page into the fax. The IRS calls this a “wet” ink signature, and the rule applies to any form sent by fax or mail.10Internal Revenue Service. Submit Forms 2848 and 8821 Online
If you need immediate processing, for instance while on the phone with an IRS employee who needs to talk to your representative, you can fax the wet-signed form directly to that employee during the call. For matters where speed matters less, the IRS runs an online portal for Forms 2848 and 8821 that does accept electronic signatures.10Internal Revenue Service. Submit Forms 2848 and 8821 Online
Sending the Fax and Keeping Proof
You can send from a physical fax machine, a multifunction printer, or an online fax service. From a machine, load the cover sheet first, check page orientation (upside-down pages are common and the IRS won’t flip them), and dial the full number with a leading 1 for long distance. Wait for the confirmation page to print before walking away. On multi-page transmissions, watch the feed for sheets sticking together.
Online fax services accept PDF uploads and transmit through the internet. If you go this route, you’re handing your Social Security Number and financial documents to a third party. The IRS itself warns taxpayers to review the privacy and security policies of any online fax service before using it.6Internal Revenue Service. Understanding Your CP2000 Series Notice Taxpayer information you send to the IRS is protected under federal confidentiality rules, but those protections don’t extend to the third-party service.11Office of the Law Revision Counsel. 26 U.S. Code 6103 – Confidentiality and Disclosure of Returns and Return Information
Whichever method you use, scan documents as high-resolution PDFs. Black-and-white at 300 DPI or higher tends to produce the cleanest results. The IRS prefers typed entries in black ink over handwriting because its scanners read typed text more reliably.12Internal Revenue Service. 2025 General Instructions for Certain Information Returns
The IRS has imposed a 100-page-per-transmission limit for at least some fax submissions.13Internal Revenue Service. Temporary Procedure to Fax Automatic Consent Forms 3115 Due to COVID-19 If your submission runs long, split it into batches with a cover sheet on each noting “Batch 1 of 2,” and so on. Most notice responses come in well under that limit.
Confirmation Is Your Only Proof
The IRS does not send an acknowledgment fax or confirmation email. Your immediate proof is the transmission report the fax machine or service generates when the send completes. A status of “OK” or “Success” means the receiving machine accepted the transmission. Print or save that report and keep it with your records.
This matters if the IRS later says it never received your response. One caveat: the “timely mailed, timely filed” rule under Treasury Regulation 301.7502-1 applies to U.S. mail and designated private delivery services, not to fax transmissions.14eCFR. 26 CFR 301.7502-1 – Timely Mailing of Documents and Payments A fax confirmation doesn’t carry the same legal presumption as a certified mail receipt. It’s still useful evidence, but don’t assume a successful transmission protects a deadline the way certified mail would. When a hard deadline is at stake and you have time, consider certified mail as a backup or supplement.
The Document Upload Tool Is Often Faster
For many notice responses, faxing is no longer the fastest option. The IRS Document Upload Tool lets you submit documents through a secure portal, and it’s worth checking before you look for a fax machine.
The tool covers responses to IRS notices and letters. Many recent notices include a unique access code and link that take you straight to the upload page. If your notice doesn’t include an access code, you can still use the tool by entering the notice or letter number, along with your name and taxpayer identification number.15Internal Revenue Service. IRS Document Upload Tool
The tool accepts JPG, PNG, and PDF files, with a maximum of 15 MB per file, up to 40 files per upload, and up to 120 pages per file.16Internal Revenue Service. Revised Interim Guidance on Document Upload Tool Like faxing, you can’t file a tax return through it. The IRS keeps expanding the notices eligible for digital response, so check whether yours qualifies before defaulting to fax.17Internal Revenue Service. IRS Expands Secure Digital Correspondence for Taxpayers
Notices with an access code typically give you 30 days from the notice date to use the upload tool. If you miss that window, faxing and mail remain available.