Treaty detail
United States - Portugal tax treaty
A practical treaty page built around the official treaty text, key withholding categories, permanent-establishment rules, and article-level summaries.
Signed
1994-09-06
Effective
1995-12-18
Articles seeded
6
Withholding snapshot
Dividends
Individual rate: 15% · Corporate rate: 5%
The 5 percent corporate rate generally depends on direct ownership of at least 25 percent of the capital of the dividend-paying company. Beneficial-ownership and qualifying-resident conditions apply and require article-level review.
Interest
Rate: 10%
The treaty generally caps source-country interest withholding at 10 percent, with exceptions for certain government, central-bank, and qualifying-institution interest categories. Article-level review is required.
Royalties
Rate: 10%
The treaty generally caps source-country withholding on qualifying royalties at 10 percent across the major copyright, patent, and know-how categories.
Permanent establishment
Construction threshold: more than 9 months
Dependent-agent analysis remains important where a person habitually concludes contracts on behalf of the enterprise under the treaty wording.
Other treaty flags
The Portugal treaty generally allocates private pensions to the residence state. Government pensions and social-security payments follow distinct rules and deserve article-level review.
Seeded article summaries
Article 4
Residence
Defines treaty residence and gates access to reduced withholding and business-profit protection.
Residence under the Portugal treaty must be read alongside the limitation-on-benefits article. The combined analysis determines whether treaty benefits actually apply in a given fact pattern.
Article 5
Permanent Establishment
Sets the business-presence threshold for source-country taxation.
The Portugal treaty includes a construction-and-installation PE threshold of more than nine months, which is shorter than the more common twelve-month rule. Dependent-agent and preparatory-activity rules apply and require article-level review.
Article 7
Business Profits
Generally reserves business profits to the residence state absent a permanent establishment in the other state.
This is the operating-rule article once the PE analysis is complete. The shorter PE threshold under the Portugal treaty means more construction and project-based fact patterns may cross into source-country taxation.
Article 10
Dividends
Provides reduced source-country withholding rates for qualifying dividends.
The Portugal dividend article supports the standard 15 percent and 5 percent rates with conditions that include direct-ownership thresholds at 25 percent of capital.
Article 11
Interest
Generally caps source-country interest withholding at 10 percent.
Interest under the Portugal treaty is subject to a 10 percent cap rather than the zero result common in newer U.S. treaties. Beneficial-ownership and category-specific rules apply.
Article 12
Royalties
Caps source-country withholding on qualifying royalties at 10 percent.
The royalty article in the Portugal treaty applies a 10 percent cap across the major royalty categories, rather than the zero result found in many newer U.S. treaties.
Official text
Other treaties involving these jurisdictions
Computed from the cross-reference graph. Links open the related entity on this site.
This entry cites
- TreatyUS–GB treaty
- TreatyUS–CA treaty
- TreatyUS–DE treaty
- TreatyUS–FR treaty
- TreatyUS–JP treaty
- TreatyUS–NL treaty
- TreatyUS–AU treaty
- TreatyUS–KR treaty
Primary sources
- Portugal treaty documents pageVerified 2026-05-20
- Official U.S.-Portugal treaty PDFVerified 2026-05-20
- IRS Tax Treaty Table 1Verified 2026-05-20
Important disclaimer
This library is for general tax education only. Always verify filing obligations, due dates, and tax consequences against the cited primary source or with a qualified tax professional.