A small green or white card given to all nonimmigrants when they enter the united states. the i-94 card serves as evidence that a nonimmigrant has entered legally. it is stamped with a date indicating how long the nonimmigrant may stay for that particular trip. (it is this date–and not the expiration date of the visa — that must be followed in determining when the immigrant must leave.) a new i-94 card with a new date is issued each time the nonimmigrant legally enters the united states. canadian visitors are not normally issued i-94 cards.