The IRS EIN fax number for domestic applicants is 855-641-6935. This guide covers every fax number for Form SS-4, the 8-step faxing process, processing times, and the most common mistakes that delay your EIN.
Frequently Asked Questions
What is the IRS fax number for an EIN application?
For domestic applicants (U.S. address), fax Form SS-4 to 855-641-6935. International applicants faxing from within the U.S. use 855-215-1627. Faxing from outside the U.S.? Use 304-707-9471 (not toll-free). Processing takes approximately 4 business days.
How long does it take the IRS to process a faxed EIN application?
The IRS processes faxed Form SS-4 applications in approximately 4 business days and faxes your EIN back to the number you provided on your cover sheet. A CP-575 confirmation letter also arrives by mail within 4–6 weeks regardless of your application method.
Can I get an EIN faster than faxing?
Yes. The IRS online EIN application at irs.gov/EIN issues your EIN immediately upon approval. Online is available to U.S.-based applicants whose responsible party has a valid SSN, ITIN, or EIN. If you cannot use the online tool, fax is the next fastest option at roughly 4 business days.
What do I need to include with my Form SS-4 fax?
You must include a cover sheet with your business name, complete contact information, and — critically — your return fax number. Without a return fax number, the IRS has no way to send your EIN back to you. Number every page of the fax sequentially and sign Form SS-4 before sending.
What if I don't receive my EIN after faxing?
If you haven't received a fax back after 4 business days, call the IRS Business & Specialty Tax Line at 1-800-829-4933 (Monday–Friday, 7 a.m.–7 p.m. local time). Have your SS-4 details and fax confirmation page ready. Do not re-fax the application unless you confirm the IRS never received it.