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Institution fax numbers

Fax numbers international users often need — U.S. IRS forms, USPTO, WIPO and more. Verify on the official page before sending.

InstitutionCategoryCityFax number
IRS — EIN application (Form SS-4), international applicantsGovernmentUSA+1 304-707-9471Send with FaxTo
IRS — EIN application (Form SS-4), U.S. applicantsGovernmentUSA+1 855-641-6935Send with FaxTo
IRS — Power of Attorney (Form 2848 / 8821), filers abroadGovernmentUSA+1 304-707-9785Send with FaxTo
IRS — Taxpayer Advocate Service (Form 911)GovernmentUSA+1 855-828-2723Send with FaxTo
IRS — International taxpayer questionsGovernmentUSA+1 681-247-3101Send with FaxTo
USPTO — Patent correspondence (central fax)GovernmentUSA+1 571-273-8300Send with FaxTo
WIPO — Headquarters correspondenceGovernmentGeneva, CH+41 22 733 54 28Send with FaxTo

Numbers were compiled from each institution’s official website (e.g. IRS, USPTO, WIPO) in July 2026 and may change — the IRS in particular changes fax numbers without notice. Click the institution name to open the source and verify before sending.

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