There are a number of situations in which it is recommended that LPRs obtain a reentry permit before traveling abroad. Generally, if you will (or potentially could) remain outside of the U.S. for a period of more than one (1) but less than two (2) years then you should definitely consider obtaining a reentry permit in order to maintain your permanent residency (green card). Alternatively, if you are traveling frequently in and out of the U.S., especially if you spend considerable periods of time abroad, even though each of your individual stays outside of the U.S. is less than one year, a reentry permit would help you demonstrate your continued intent to maintain U.S. permanent residency, but also help you avoid questioning at the U.S. border.

You may also want to get a reentry permit if you plan on traveling outside the U.S. and cannot, or do not wish to get a passport from your home country. Some LPRs based on asylum do not actually have foreign passports and for them, the only travel document permitting them to leave the U.S. is the reentry permit. As a result, many countries throughout the world allow you to use a reentry permit much like you would use a passport – placing necessary visas, and entry and exit stamps in the permit – so you may use it as your main travel document.