Make sure to keep it in a safe place so it doesn't get lost. Students and scholars are required to keep the passport entry stamp or I-94 card for the duration of their visit. Students and scholars on F or J status should receive a stamp marked "D/S" or "duration of status." This means that they may remain in the United States as long as they are properly maintaining status and their I-20 (F-1) or DS-2019 (J-1) has not expired. On the passport admission stamp or the paper I-94 card, the inspector writes either a date or "D/S" (duration of status). In these cases, you will not receive an electronic I-94 record.
Nonimmigrants who arrive in the United States by crossing a land border will continue to receive the paper I-94 card. To access this record, visit the CBP's website. Your electronic I-94 record should be printed immediately after arrival. If a student or scholar has received a passport admission stamp, there will also be an electronic I-94 record. Nonimmigrants who arrive in the United States by air or sea should be issued the passport admission stamp. This indicates how long a student or scholar is allowed to stay in the United States and proves that they arrived in the country legally. When entering the United States as a nonimmigrant, the Customs Border Protection (CBP) officer examines your passport and visa and then issues either a passport admission stamp or a small white card called the Form I-94. GET YOUR MOST RECENT ELECTRONIC I-94 HERE! The I-94: Proof of Legal Entry into the United States