EIN Fax vs Online: Why the IRS Forces Foreign Founders to Fax

The IRS online EIN portal launched in 2007 as part of the agency's modernization push. It was designed for US-resident applicants verifying through SSN. ITIN was added later as a secondary verification path for US-resident-with-ITIN cases (typically dependent spouses, certain residents without SSN).

The online portal was never extended to non-resident applicants because the IRS lacks an identity verification path that does not depend on SSN/ITIN. Adding such a path would require coordinating with foreign tax authorities, which the agency has not prioritized.

The fax channel for Form SS-4 was the original mechanism for all EIN applications before the online portal. When the portal launched, the fax channel stayed for cases that could not use the online system: non-residents, large/complex business structures requiring narrative attachments, and EINs for trusts or estates.

The IRS International EIN unit (the specific team handling non-resident applications via fax) is housed at the IRS Philadelphia Service Center. They process applications in batch and respond by fax with CP575 (EIN assignment letter) or 147C (replacement letter).

The IRS does allow EIN application by phone (toll-free 1-267-941-1099 for international applicants). But the phone process has drawbacks:

• Phone wait times can be 1-4 hours during peak periods
• Time zone conflicts for non-US applicants
• You need to verbally provide all Form SS-4 information
• No paper trail (CP575 still arrives by mail later)
• IRS phone reps sometimes refuse non-resident requests

Fax is more reliable. You submit complete documentation in writing. IRS processes when they get to your batch. CP575 comes back by fax (no waiting for mail).

1. Day 0: Fax sent via your fax service (eFax, RingCentral, etc.)
2. Day 1-3: IRS confirms receipt and queues for review
3. Day 4-7: IRS reviewer processes the application, verifies entity details against state SoS records
4. Day 8-10: IRS faxes back CP575 (EIN assignment letter)
5. Day 10+: You have your EIN, can open Mercury, Stripe, etc.

Not on any announced timeline. The IRS has discussed modernizing non-resident services in various reports but no concrete plan exists. So the fax channel remains the standard. WyomingLLC files via fax for every customer because it is the only reliable path.