U.S. citizens are taxed on their worldwide income, no matter where they work. Some taxpayers may qualify for the foreign earned income exclusion, foreign housing exclusion, or foreign housing deduction, if their tax home is in a foreign country and they are either a bona fide resident of a foreign country or countries for an uninterrupted period that includes an entire tax year, or are physically present in a foreign country or countries for at least 330 full days during any period of 12 consecutive months. If the taxpayer is temporarily away from his or her tax home in the United States on business (less than a year), the taxpayer may qualify to deduct away from home expenses (for travel, meals, and lodging ) but would not qualify for the foreign earned income exclusion.

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