If you are a U.S. lawful permanent resident (green card holder), and you need to spend a year or more outside the United States, you would be wise to get a travel document called a "reentry permit" for your return.
Although you are certainly allowed to travel, and a green card (plus your own passport) is normally all you need for entry upon returning (and you'll still need to carry those), the situation changes a bit if you spend a long time outside the United States. The immigration authorities will wonder whether you meant to abandon your U.S. residence. In fact, after one year, your green card alone becomes invalid for U.S. entry. A reentry permit helps prove that you did not mean to give up your green card.
A reentry permit is also useful for another purpose: when you cannot, or do not wish to, get a passport from your home country. The permit (which looks very much like a passport) can be used in its place.
Here are some common questions and answers to help you better understand the reentry permit process.
A reentry permit is typically valid for two years from its date of issue. There's an exception for conditional residents whose residency expiration date will come before that amount of time is up. They will be given a reentry permit good for only as long as their conditional residence lasts, and will be expected to apply for and obtain U.S permanent residence before requesting any more reentry permits.
You cannot extend the time on your reentry permit. If it expires, but you haven't yet finished with whatever took you outside the U.S., you will need to return to the U.S. and apply for a new one.
You must apply for your reentry permit before leaving the United States. The first step in this process is to fill out Form I-131, issued by U.S. Citizenship and Immigration Services (USCIS). This form is used for various different types of applications for travel documents, such as for people applying for Refugee Travel Documents, so simply don't fill out the portions that don't apply to you.
You'll also need to gather the following to include when submitting your Form I-131.
You'll need to submit your application to USCIS by mail, using the address given on its website with the instructions for Form I-131.
It typically takes USCIS 90 days or more to make a decision on a reentry permit. For that reason, USCIS says that you should apply well in advance of your travel -- at the very latest, 60 days before you depart. You can check the status of USCIS's processing of your permit on the USCIS "My Case Status" Web page.
As long as USCIS has received your application and called you in for your fingerprinting (biometrics) appointment, however, you do not need to wait in the U.S. until the reentry permit is approved. You can ask that it be sent to an overseas U.S. immigration office or consulate.
A reentry permit can be denied for any of various reasons, including if you forget to include the appropriate documents or fee. One obvious reason for denial is if you have a reentry document already and it is still valid. Of course, if you don't actually have it any more, because it was lost, stolen, or destroyed, you should explain that in your application, and USCIS can send you a new one.
People who have been denied a reentry permit can make an appeal with 33 days upon receipt of the denial letter. All instructions and requirements for the appeal will be stated in the letter.
Yes. If you depart United States after having become inadmissible, or you become inadmissible while you're away, you may be denied entry. Examples of ways that you might become inadmissible include committing a crime, getting involved in terrorist activity, developing a health problem that's seen as a risk to people in the U.S., and many other reasons.
In fact, it is even possible for the border officials who meet you upon your return to the U.S. to exclude you from entry based on you having abandoned your U.S. residence. Although the reentry permit creates a presumption that you did not intend to abandon your residence, if the official sees clear indications that you really were making your home elsewhere, you can be refused entry.
If you have any questions about your need for a reentry permit or the process of applying for such a permit, contact an experienced U.S. immigration attorney. The attorney can help you with the application and provide you with the guidance you need to protect your right to return to the United States.