Internal Revenue Service (U.S. Taxes)

If you are a U.S. citizen or resident alien living or traveling outside the United States, you generally are required to file income tax returns, estate tax returns, and gift tax returns, and pay estimated tax in the same way as those residing in the United States. Your worldwide income is subject to U.S. income tax, regardless of where you reside, even if may not owe any tax because of income exclusion or tax credit.

Information on filing your tax returns while abroad can be found at  https://www.irs.gov/individuals/international-taxpayers/frequently-asked-questions-about-international-individual-tax-matters#ApplicationforIRSITIN