U.S. law requires males between the ages of 18 to 25 to register for the selective service regardless of their legal status. Thus, if you or someone you know currently does not have legal status in the U.S., but at some point might be able to become a legal permanent resident and later eligible to become a U.S. citizen before they turn 31 years old, they'll need to prove they registered for the selective service before they turned 26 years old. If not, they'll probably need to wait until they turn 31 years old before applying for naturalization. You can register online at https://www.sss.gov/register/. For more information about the immigration implications of not registering for selective service, please call us at (512) 488-3970.