New tax treaties and protocol. The United States has exchanged instruments of ratification for new income tax treaties with Bulgaria and Iceland and a new protocol to the income tax treaty with Canada. The provisions of these treaties and protocol are included in the appropriate areas of this publication. The effective dates are as follows: Bulgaria. The provisions for withholding tax at source are effective for amounts paid or credited on or after January 1, 2009. For other taxes, the treaty is effective for tax periods beginning on or after January 1, 2009. Canada. The provisions for withholding tax at source are generally effective for amounts paid or credited on or after February 1, 2009. For other taxes, the protocol is generally effective for tax years beginning on or after January 1, 2009. Certain provisions, none of which are discussed in this publication, have different effective dates.Publication 597, Information on the United States—Canada Income Tax Treaty (Rev. April 2009), provides a more detailed explanation of the treaty as amended by the protocol. Iceland. The provisions for withholding tax at source are effective for amounts derived on or after January 1, 2009. For other taxes, the new treaty is effective for tax years beginning on or after January 1, 2009. An individual who was otherwise entitled to treaty benefits under Article 21 (Teachers) of the former treaty can continue to apply those provisions. A person entitled to benefits under the former treaty can elect to have that treaty apply in its entirety for a twelve-month period following the date the new treaty would otherwise apply.

Disclosure of a treaty-based position that reduces your tax. If you take the position that any U.S. tax is overruled or otherwise reduced by a U.S. treaty (a treaty-based position), you generally must disclose that position on your affected return. See Application of Treaties, later.

U.S.–U.S.S.R. income tax treaty. The U.S.–U.S.S.R. income tax treaty remains in effect for the following members of the Commonwealth of Independent States: Armenia, Azerbaijan, Belarus, Georgia, Kyrgyzstan, Moldova, Tajikistan, Turkmenistan, and Uzbekistan. That treaty will remain in effect until new treaties with these individual countries are negotiated and ratified. Provisions of the U.S.–U.S.S.R. income tax treaty are discussed in this publication under Commonwealth of Independent States.

U.S.–China income tax treaty. The U.S.–China income tax treaty does not apply to Hong Kong.

U.S.–United Kingdom income tax treaty. Generally, the treaty is effective for tax periods beginning on or after January 1, 2004. However, an individual who was otherwise entitled to treaty benefits under Article 21 (students and trainees) of the former treaty can continue to apply that provision.

This publication will tell you whether a tax treaty between the United States and a particular country offers a reduced rate of, or possibly a complete exemption from, U.S. income tax for residents of that particular country.

Tables in the back of this publication show the countries that have income tax treaties with the United States, the tax rates on different kinds of income, and the kinds of income that are exempt from tax.