If you are planning to enter the United States by legally crossing a land border from Mexico or Canada, using a document such as a border crossing card, a nonimmigrant (temporary) visa such as a tourist, business visitor, or student visa, or the Visa Waiver Program (VWP), get ready to experience a common phenomenon: Visitors can spend hours, often in a long line of cars, waiting to get through the U.S. border inspection point.
That's because a U.S. Customs and Border Protection (CBP) officer must talk to all would-be entrants, evaluate whether their entry documents are real and valid, and potentially order further interviews or search their belongings before making a decision.
Only after all of this is done might the CBP officer approve the entrant and create a I-94, which shows the date by which the person must leave the United States. Although travelers arriving at air or seaports don't receive paper I-94s (it is created online and available to them on the CBP website), land travelers continue to receive paper I-94s.
Fortunately, there's a way to get one's I-94 underway before heading toward the U.S. land border, as this article describes.
(To reiterate, this only works for land crossings; if you will be arriving in the U.S. by air or sea, the I-94 issuance process is already automated, and no advance application is offered or required.)
Unlike in years past, travelers to a U.S. border post are now able to apply and pay for their I-94 entry document online. They must take care of this within the week BEFORE presenting themselves at the U.S. border facility.
This online system lets you avoid time that you would otherwise spend providing your name and various biographic details (date of birth and country of citizenship), passport details, visa details, and your visa petition or Student and Exchange Visitor Program (SEVIS) number (if applicable).
After submitting your online application on the CBP website and paying the fee, you will receive what's called a "provisional I-94." The fee is currently (as of 2019) $6, which you can pay using PayPal or a credit or debit card.
Assuming you actually show up at the U.S. land port of entry within seven days of your application and request admission to the United States, your provisional I-94 should speed the process forward; though being "provisional," it's not the last word on whether you will be allowed U.S. entry.
You might also be asked to submit biometrics (fingerprints). You will be interviewed by a CBP officer, who will also check to see whether you have your other required documents (visa, evidence of residence and employment, and a travel itinerary). The CBP officer will hopefully then turn your I-94 from provisional to actual.
If you fail to show up within the seven days, your provisional I-94 will expire and you won't get a refund. You will probably want to apply again before entering the United States.