For immigrants arriving to the United States, the American tax system can be a very new and confusing concept. In fact, the U.S. tax system is so complex that most natural-born Americans have difficulty filing each year. As a general rule, U.S. tax law applies to you if you live in the United States or spend a significant amount of time here.

In the United States everyone with income above certain levels is expected to file a tax return. That’s not true in all countries around the world. In many countries, the government withholds taxes from paychecks, and the individual never has to directly file an income tax return. The Internal Revenue Service (IRS) is the U.S. agency responsible for collecting taxes.

Whether you are a lawful permanent resident or an undocumented immigrant, it’s important that you get a basic understanding of your tax filing obligations.