If you are a U.S. citizen or resident alien, the rules for filing income, estate, and gift tax returns and for paying estimated tax are generally the same whether you are in the United States or abroad. Your income, filing status, and age generally determine whether you must file an income tax return. If you are the dependent of another taxpayer, see the instructions for Form 1040 for more information on whether you must file a return.
A U.S. citizen or resident alien is generally subject to U.S. tax on total worldwide income. However, if you are a United States citizen or a resident alien who lives and works abroad, you may qualify to exclude all or part of your foreign earned income.
For detailed information, please refer to IRS Publication 54 Tax Guide for U.S. Citizens and Resident Aliens Abroad. If the information you need relating to this topic is not addressed in Publication 54, you may call the IRS International Tax Law hotline. The number is (267) 941-1000. Please note that this is not a toll-free number.