老皮转的帖（http://bbs.creaders.net/tea/bbsviewer.php?trd_id=1452943 ）说“美国民间对中国的捐助20%到40%免税，因此免税部分由美国政府承担”是错误的。上美国税务局网站查一下，除了因为国际条约，美国民间给加拿大一些组织的捐助可以免税，对其他外国的捐助不免税。IRS网址：https://www.irs.gov/charities-non-profits/charitable-organizations/charitable-contribution-deductions

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Foreign Organizations

The organizations listed in Tax Exempt Organization Search with foreign addresses are generally not foreign organizations but are domestically formed organizations carrying on activities in foreign countries.  These organizations are treated the same as any other domestic organization with regard to deductibility limitations.

Certain organizations with Canadian addresses listed may be foreign organizations to which contributions are deductible only because of tax treaty. Besides being subject to the overall limits applicable to all your charitable contributions under U.S. tax law, your charitable contributions to Canadian organizations are subject to the U.S. percentage limits on charitable contributions, applied to your Canadian source income.  A deduction for a contribution to a Canadian organization is not allowed if the contributor reports no taxable income from Canadian sources on the United States income tax return, as described in Publication 597.

Except as indicated above, contributions to a foreign organization are not deductible.