An extension to file is not an extension to pay tax.
Puerto Rico has its own page on this site. This page covers the remaining four US territories: the U.S. Virgin Islands (USVI), the Commonwealth of the Northern Mariana Islands (CNMI), Guam, and American Samoa. All four operate income tax systems that are wholly or partially based on the U.S. Internal Revenue Code ("mirror code" territories), so a bona fide resident generally files with the territory's own tax department instead of the IRS - which is also where an extension request goes.
| Territory | Extension mechanism | Status |
|---|---|---|
| U.S. Virgin Islands | Bona fide residents must file a paper Form 4868 with the V.I. Bureau of Internal Revenue (not the IRS) for the automatic 6-month extension. Nonresidents of the USVI with USVI-source income file separate extension requests with both the IRS and the VI BIR - the VI BIR will honor an extension timely filed with the IRS. | Confirmed - IRS Publication 570 |
| CNMI | Dual-track system. The mirror-code Northern Mariana Territorial Income Tax (NMTIT - the CNMI's equivalent of federal income tax) follows the same Form 4868/Form 7004 extension mechanics as the federal code, filed with the CNMI Division of Revenue and Taxation instead of the IRS. Separately, CNMI's own local Wage and Salary Tax and Earnings Tax have their own extension to file "as provided by regulations prescribed by the Secretary" (4 CMC sect 1815(a)) - a mechanism exists, though the statute itself does not fix a length. CNMI's local Gross Revenue Tax has no extension to file at all (4 CMC sect 1815(b)) - only a reasonable-cause penalty waiver. | Confirmed - 4 CMC sect 1815; IRS Publication 570 |
| Guam | Guam is a full mirror-code territory: 48 U.S.C. sect 1421i(a)-(b) makes the U.S. Internal Revenue Code "likewise in force in Guam" as the Guam Territorial income tax, substituting "Guam" for "United States" and the Governor for the Secretary of the Treasury throughout. Under this substitution, the same Form 4868 automatic 6-month extension mechanics apply, but the form is filed with Guam's Department of Revenue and Taxation (Guam's equivalent of the IRS) rather than with the IRS itself - the IRS's own Form 4868 filing instructions direct "permanent residents of Guam or the U.S. Virgin Islands" to Publication 570 rather than to an IRS address, grouping Guam with the already-confirmed USVI treatment. | Reasonable inference from the mirror-code statute, not a Guam-specific bulletin - Guam's Department of Revenue and Taxation site (guamtax.com) does not publish a standalone extension procedure page, and its taxpayer portal's own reference to "Form 4868" is consistent with but does not independently confirm this reading. Treat the mechanism as sound but the specific filing address/procedure as unconfirmed against a Guam-issued source. |
| American Samoa | American Samoa is not a mirror-code territory - it enacted its own local income tax code based on the Internal Revenue Code as it stood on December 31, 2010 (American Samoa Code Annotated, Title 11), and that code does not automatically update with later federal changes. A bona fide resident files two separate returns for the same year: an American Samoa territorial return (worldwide income, with the ASG Treasury Tax Office) and a U.S. return (worldwide income excluding American-Samoa-source income, with the IRS) per IRS Publication 570. The U.S. return's extension is the ordinary Form 4868 filed with the IRS - that part is confirmed. The American Samoa territorial return's own extension procedure is the unresolved piece. | Partially confirmed. The dual-filing structure and the U.S.-return extension (Form 4868 with the IRS) are confirmed via IRS Publication 570. The American Samoa territorial return's own extension mechanism is not independently confirmed this session - no ASCA Title 11 provision or ASG Treasury regulation establishing one could be located after a direct search of the ASG Tax Office site and general web search; the office's phone line ((684) 633-4181) was identified as the fallback contact but not called. Disclosed as an open item, not assumed. |