A U.S. dependent visa allows immediate family members (spouses and unmarried children under 21) to accompany or join a principal visa holder in the United States. These visas are linked to the primary visa category; for example, H-4 for H-1B holders, F-2 for F-1 students, L-2 for L-1 intracompany transferees, and J-2 for J-1 exchange visitors. Dependent visas enable families to stay together during the principal visa holder's authorized period in the U.S.