The most important error commonly made by foreigners after entry into the United States is confusing the visa, a machine-readable visa stamp bearing a photo issued into the traveler’s passport at a US Embassy abroad, with the I-94 entry/departure record, a card stapled into the passport at a US airport or border post when the traveler is admitted.
A visa is an entry document, which must be valid for admission when traveling from abroad and seeking entry into the United States. An I-94 is a status document, which defines the traveler’s visa status and length of stay permitted. Once a traveler is admitted to the United States, dates on the visa do not define how long the traveler is allowed to stay; the I-94 card is the controlling document.
For most temporary travelers, the I-94 card will show two dates: the date of admission, stamped in red by the inspecting officer, and the date the period of stay ends, handwritten or printed by the officer underneath the admission date. Some ports of entry now generate a new type of electronically-printed I-94 card, on which the end-of-stay date is printed and no content is handwritten.
Many travelers with work visas may have multiple notices of approval from USCIS with “replacement I-94s” to indicate a change or extension of status. Even if you have one or more of these, do not discard the white original I-94 card received upon last admission at a Port of Entry.
Some types of travelers (primarily students) receive an I-94 card marked “D/S”, for “Duration of Status,” instead of one that specifies a fixed end date. “D/S” refers to another, secondary status document that will determine when the lawful period of stay ends. For F-1 and M-1 students, the secondary status document is a Form I-20, issued by a US school authorized to enroll foreign students in a full-time course of study. For J-1 exchange visitors, the secondary status document is a Form DS-2019, issued by a program sponsor authorized by the U.S. Department of State.
Except for students who have quit their program and are no longer maintaining valid visa status, most are entitled to a grace period. Upon completion of the authorized course of study or practical training, F-1 students are allowed a grace period of 60 days during which they may remain in the United States. J-1 exchange visitors and M-1 vocational students have a grace period of 30 days.
Some visitors from countries that participate in the Visa Waiver Program- who are allowed to come to the U.S. as visitors without applying for a visa – are admitted without an I-94 card at all: the entry stamp at the U.S. Port of Entry is now placed directly in the traveler’s passport. Travelers under the Visa Waiver Program are admitted for 90 days only, and may not extend their stay.
There are many subtleties to status documents. If you have questions about your own status documents, consult an immigration attorney and bring the original documents for clarification.