GIIN is a Global Intermediary Identification Number assigned by the FATCA Registration System to financial institutions and direct reporting non-financial foreign entities. Those assigned a GIIN may use it to identify themselves to withholding agents and tax administrations for FATCA reporting.

FATCA requires foreign financial institutions (FFIs) to report to the IRS information about financial accounts held by U.S. taxpayers, or by foreign entities in which U.S. taxpayers hold a substantial ownership interest.

Taxpayers living in the United States. You must file Form 8938 if you must file an income tax return and: You are unmarried and the total value of your specified foreign financial assets is more than $50,000 on the last day of the tax year or more than $75,000 at any time during the tax year.

FATCA generally requires Americans to report all their foreign assets when filing their taxes. However, there are some types of assets that are exempt from this requirement—including real estate located in the United States and certain retirement plans meaning that some expats have FATCA exemption.

You must file FATCA if your assets exceed the following values: Single taxpayers living abroad: $200,000 on the last day of the tax year or $300,000 at any point during the year. Married taxpayers living abroad: ... Single taxpayers living in the US: ... Married taxpayers living in the US:

An interest in the social security, social insurance, or another similar program of a foreign government. If you have an investment interest in the social security, social insurance, or a foreign government program of a similar nature, you'll not have to report such investments under FATCA's regulations.

FATCA applies to individual citizens, residents, and non-resident aliens. Residents and entities in U.S. territories must file FBARs but don't need to file FATCA forms.