There is no single IRS fax number for Form 8862. The correct number is the one printed on the IRS notice you received — most often a CP75 — because each IRS campus and examination unit uses its own dedicated fax line. Sending your form to any other IRS fax number routes it to a department with no connection to your open case, and there is no reliable internal rerouting.
Where the Fax Number Appears on Your Notice
When the IRS audits a tax credit through a correspondence examination, the notice it sends identifies which credits are under review and lists both a fax number and a mailing address for the campus handling your case.1Internal Revenue Service. IRS Audits The fax number usually sits on the first or second page, inside the contact information block near the response deadline.
That number is the only one you should use for Form 8862 and the documents backing up your credit claim. It feeds directly to the team working your file.
If You No Longer Have the Notice
Call the phone number listed on the notice itself. If your audit letter shows 866-897-0177 or 866-897-0161, you can also check your audit status through your online IRS account under the “Records and Status” tab.1Internal Revenue Service. IRS Audits If you have no IRS correspondence at hand at all, call the general IRS line at 800-829-1040 and ask to be routed to the examination unit handling your return.
The Document Upload Tool Is Often Faster Than Fax
The IRS has been replacing fax with its online Document Upload Tool, and recent updates to the Internal Revenue Manual have removed fax-related procedures in favor of the upload tool across correspondence examination units.2Internal Revenue Service. Campus Examination Telephone Contacts Many newer notices now print a QR code and URL for the upload tool and no fax number at all.
To use the tool you need either the access code printed on your notice or the notice number itself, plus your name and Social Security number or taxpayer identification number.3Internal Revenue Service. IRS Document Upload Tool If your notice includes an access code, scan the QR code or go to the URL it shows. If it doesn’t, open the tool through IRS.gov and enter the notice or letter number manually. Select the correct notice type from the dropdown — the wrong selection can cause delays.
The IRS has acknowledged that documents submitted through the upload tool reach the assigned examiner faster than faxed or mailed documents, while still being worked in the same first-in, first-out order.4Internal Revenue Service. Document Upload Tool – YouTube Video Text Script You also get an on-screen confirmation page, which serves as your proof of delivery. For most taxpayers responding to a CP75 in 2026, the upload tool is the fastest and most reliable submission method.
How to Fax Form 8862 Correctly
Fax is still an option wherever the IRS notice provides a fax number.1Internal Revenue Service. IRS Audits A failed transmission on a ticking deadline is avoidable with a little preparation.
Put a cover sheet first. The IRS instructs taxpayers to include the reply cover sheet with any documents they send.5Internal Revenue Service. Audits by Mail – What To Do Your cover sheet should carry your full name, Social Security number or taxpayer identification number, the IRS notice number you are responding to, the date, and the total page count. That information helps IRS staff match your fax to the correct case file.
Fax during off-peak hours (early morning or late evening) to reduce the chance of busy signals. Check every page for legibility before feeding it through — blurry or cut-off pages are treated as if they were never sent. Once the transmission completes, keep the confirmation page. That printout, showing date, time, and number of pages sent, is your only proof of delivery.
Mailing Form 8862 Instead
Mail is always available. Send Form 8862 and your supporting documents to the address printed on your IRS notice. Use certified mail with return receipt requested, which gives you a postmarked date proving when you mailed the documents and a signed confirmation when the IRS receives them.6Taxpayer Advocate Service. Options for Filing a Tax Return The IRS also recognizes certain private delivery services, such as specific FedEx and UPS options, for meeting timely-filing deadlines.7Internal Revenue Service. Private Delivery Services
The downside is speed. Processing takes longer than fax or the upload tool, and you are working against a deadline.
Why the Submission Method Matters: The 30-Day Deadline
A CP75 notice gives you 30 days from the date on the notice to submit your supporting documentation.8Internal Revenue Service. CP75 Notice Miss that window and the IRS will disallow the credits under review. You may then owe additional tax, and the IRS will issue a statutory notice of deficiency (the “90-day letter”) giving you a final chance to petition the U.S. Tax Court before the assessment becomes final.
A fax or an upload delivers the same day. Certified mail can take a week or more to arrive. If your deadline is close, fax or upload first and mail a backup copy afterward. There is no penalty for submitting the same documents through multiple channels, and it protects you if one transmission fails.
Make Sure Form 8862 Is Actually What You Need to File
Form 8862 covers five tax credits: the Earned Income Credit, the Child Tax Credit, the Additional Child Tax Credit, the Credit for Other Dependents, and the American Opportunity Tax Credit.9Internal Revenue Service. About Form 8862, Information To Claim Certain Credits After Disallowance You file it when the IRS previously reduced or disallowed one of these credits for any reason other than a math or clerical error, and you now want to claim that credit again. The form attaches to your tax return for the year you are reclaiming the credit; without it, the IRS automatically rejects the claim for that filing year.10Internal Revenue Service. Instructions for Form 8862
A couple of boundaries worth knowing before you send anything.
A CP09 notice is not a CP75. A CP09 tells you that you may qualify for the Earned Income Credit but did not claim it on your return.11Internal Revenue Service. Understanding Your CP09 Notice Form 8862 responds to a disallowance, not to a CP09 suggesting you claim a credit you missed.
And if the IRS has imposed a ban period on your credit — two years for reckless or intentional disregard of the rules, ten years for fraud12Office of the Law Revision Counsel. 26 USC 32 – Earned Income — do not file Form 8862 during that window. The IRS will reject it. The instructions are explicit on this point.10Internal Revenue Service. Instructions for Form 8862 The one exception is filing Form 8862 specifically to appeal the ban itself, following the appeal instructions in the form.