As a conditional or permanent U.S. resident, foreign travel is one of the important rights that you enjoy. But certain important rules that you should be aware of apply, regarding:
As the term "resident" suggests, your status comes with the expectation that you will reside—that is, make your home—in the United States. If you make your home outside the U.S., you could lose your green card.
Officers of Customs and Border Protection (CBP) are on the front lines of deciding whether returning green card holders are actually living in some other country. The officer will, upon your return from foreign travel, ask when you left the U.S., what you were doing while you were away, and where you make your home.
If you were outside the U.S. for more than one year, and did not get advance permission to return before leaving, the law presumes that you abandoned your permanent residence, and invalidates your green card as a travel document. You might not even allowed to board an aircraft or other form of travel to the United States.
To challenge the abandonment presumption, you will probably have to either convince airline or other officials to contact U.S. Customs and Border Protection (CBP) on your behalf or attempt to enter at a U.S. land border. Regardless of which border or port of entry you ultimately arrive at, you will likely go through several levels of inspection and might ultimately be given a notice to appear in immigration court (an NTA). In that case you'd be let in provisionally, and have to convince an immigration judge that you did not abandon your status.
Does all this mean you're safe as long as you return to the U.S. once a year? No! It's all a matter of where you actually live, regardless of whether you intend to go back to the United States at some point. If you've sold your U.S. house, enrolled the kids in school overseas, and quit your U.S. job, a CBP officer could, in theory, find that you abandoned your residence even if you attempt to reenter the U.S. after one day away.
Long trips away are seen as a big clue that you might have abandoned your U.S. residence. Making many trips outside the U.S. creates a risk of being found to have abandoned your residency if, over the course of several years, you spend more time outside the U.S. than within it. Trips outside the U.S. for more than six months are treated more seriously than shorter trips, but even shorter trips can raise questions if you make so many that it looks like you are merely visiting the U.S. instead of living here.
If the border officer wonders whether you abandoned your permanent resident status, in addition to your length of time outside the U.S., the officer may look into whether you:
If you are returning after a trip of several months, you can make your entry to the U.S. easier by bringing copies of documents that show that your home base is still in the United States. These documents could include your U.S. tax returns, home lease, evidence of employment, or other relevant documents.
In a border official tells you that you have abandoned your permanent residence, he or she will probably let you back into the U.S., but place you into removal (deportation) proceedings. The officer's decision is not final; you will have the right to present your case in immigration court. Only an immigration judge has the authority to make a final decision about whether you abandoned your status. You can also appeal the judge's decision. For help if you are placed into removal proceedings, contact an attorney.
Get permission before leaving. If you know before your departure that you will have to spend more than a year outside the U.S., apply for what's known as a reentry permit. Use USCIS Form I-131, Application for Travel Document, available for free download on the USCIS website. Be sure to check Box a in Part 2 for reentry permits. You will have to explain to USCIS the purpose of your trip and how much time you have already spent outside the United States. You do not need to wait for the permit to be approved before departing the U.S., but you do need to get your biometrics (fingerprints, photo, and signature) taken for the permit before you leave. USCIS will schedule you for a biometrics appointment after you submit the I-131; usually some weeks after. For more information, see Reentry Permits: Preparing Green Card Holders for Long Absences from the U.S.