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Country guide

United States Minor Outlying Islands

The United States Minor Outlying Islands are not identified in IRS territory-tax guidance as having a separate autonomous territory tax system and do not issue UM-specific Tax Identification Numbers. U.S. federal TINs are handled as United States identifiers, not as native UM identifiers.

UM UMI TIN guidance Last reviewed 2026-06-05
TIN status

No separate local TIN format is published for validation.

  • 1 IRS U.S. territory tax guidance identifies American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the U.S. Virgin Islands for separate territory tax-return and residency rules; it does not identify the United States Minor Outlying Islands as a separate territory tax system.
  • 2 Do not create separate UM entries for U.S. federal identifiers such as SSNs, ITINs, or EINs; those identifiers belong to the United States TIN system when applicable.
  • 3 IRS FATCA country-code material includes UM as a country or jurisdiction code, but that is not evidence of a UM-issued TIN.