Permanent residents can travel abroad with their permanent resident cards (green cards). But they cannot remain abroad for a year or more and return to the country with just their green cards. Permanent residents who plan to travel to foreign countries and remain there for a year and more, must get re-entry permits prior to leaving the United States. They need to apply for re-entry permits by filing the USCIS Form I-131, Application for Travel Document.
Conditional residents and the permanent residents can both apply for these documents to travel abroad. These permits will allow legal residents to apply for admission into the country. Legal residents who hold valid travel documents need not get returning resident visas from overseas U.S. embassies or consulates to travel back to the United States.
It must be remembered that these documents do not guarantee entry into the United States. To gain admission into the country, permanent residents returning from their trips must be admissible into the country. However, these re-entry permits will help them to establish that they intend to remain permanently in the country.
Permanent residents who remain abroad for two years and more may not be able to travel to the United States with their re-entry permits. In case they stay abroad for more than two years, they need to apply for returning resident visas at U.S. embassies or consulates abroad. SB-1 returning resident visas will help them to get into the United States.
Green card holders can travel abroad and their temporary travel will not affect their permanent resident status. United States grants permanent resident status to foreign nationals who wish to make the country their permanent home. Those who stay abroad for an extended period of time are likely to lose their legal status in the country. Hence, people who wish to retain their status in the country and travel abroad temporarily, can get re-entry permits prior to their departure. Brief trips may not be problematic but they can be on the safer side it they get re-entry permits prior to leaving the United States, if they have plans to stay abroad for a year and more but not more than 2 years.