The process for obtaining or updating a Form I-94, which records the arrival and departure of non-U.S. citizens entering the United States, can vary in length depending on several factors. The Form I-94 plays a crucial role in documenting legal entry and maintaining lawful status in the U.S., so understanding the timeline is important for travelers and visa holders.

For most travelers arriving in the United States by air or sea, the process of obtaining a Form I-94 is fairly straightforward and occurs automatically. When you arrive at a U.S. port of entry, a U.S. Customs and Border Protection (CBP) officer will review your travel documents, such as your passport and visa. If everything is in order, the officer will admit you into the country and generate an electronic Form I-94, which records the details of your entry, including the date you arrived and the date by which you must leave the U.S. While the electronic Form I-94 is generally available within a day, there can be delays in certain situations. For instance, if there are discrepancies in your travel documents or if you are subject to additional inspection at the port of entry, it might take longer for your I-94 information to be processed and uploaded to the system. In such cases, it may take several days before you can access your I-94 online. 

For travelers entering the U.S. at a land border or those in certain other circumstances, a paper Form I94 may be issued. This process is typically more time-consuming than the electronic version. Upon arrival, you may be required to complete the form manually and submit it to the CBP officer for processing. The officer will then stamp your form and your passport. If you lose your Form I-94 or need to update it due to a change in your visa status, the process can take even longer. To replace or update your I-94, you must file Form I-102, Application for Replacement/Initial Nonimmigrant Arrival-Departure Document, with U.S. Citizenship and Immigration Services (USCIS). Processing times for Form I-102 can vary, but it typically takes several weeks to a few months to receive a new or updated I-94. 

If you need to extend your stay in the U.S. beyond the expiration date on your Form I-94, you must file Form I-539, Application to Extend/Change Nonimmigrant Status, before your current I-94 expires. The processing time for Form I-539 can be lengthy, often taking several months. 

Lastly, when leaving the U.S., if you were issued a paper Form I-94, you must surrender it to the airline or CBP officer.