IRS tax forms
Internal Revenue Service / International Centralized Authorization File team
Submit international Form 8821 tax information authorization using the U.S. toll-free route
Use the number only for the documented purpose and routing rule below.
This listing does not guarantee delivery, processing, acceptance, or deadline treatment. Recheck the official instructions before sending.
Route decision
Is this the right fax route?
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- 01 Purpose
- Submit international Form 8821 tax information authorization using the U.S. toll-free route
- 02 Region or eligibility
- APO or FPO addresses, American Samoa, the Commonwealth of the Northern Mariana Islands, Guam, the U.S. Virgin Islands, Puerto Rico, a foreign country, or otherwise outside the United States.
- 03 Required form or document
- Completed and signed Form 8821, Tax Information Authorization.
Submission notes
What to put on the route.
Routing instructions
Use the International CAF Team for the listed international, territory, APO, and FPO addresses. Use this toll-free number when it is reachable from the sender location.
Official source and check date
Recheck the route before sending.
- Recipient
- Internal Revenue Service
- Fax
- 855-772-3156
- Last checked
As of August 24, 2026, the linked Internal Revenue Service source listed this number for the purpose shown. Just One Fax is not affiliated with or endorsed by Internal Revenue Service.
Before transmission
Questions to answer before sending.
What is the Internal Revenue Service fax number for this purpose?
855-772-3156 is the fax number published in the cited official source for this specific purpose: Submit international Form 8821 tax information authorization using the U.S. toll-free route. Recheck the source immediately before sending.
How do I know whether this is the right regional route?
APO or FPO addresses, American Samoa, the Commonwealth of the Northern Mariana Islands, Guam, the U.S. Virgin Islands, Puerto Rico, a foreign country, or otherwise outside the United States.
What should I send to this fax number?
Completed and signed Form 8821, Tax Information Authorization. Use the International CAF Team for the listed international, territory, APO, and FPO addresses. Use this toll-free number when it is reachable from the sender location.
Does this listing guarantee acceptance?
No. The linked source listed this route on August 24, 2026, but only the recipient can determine delivery, eligibility, processing, acceptance, or deadline treatment.
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Send to 855-772-3156