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This is a very common question and can lead to misunderstandings. In this guide, you will learn what each one means and how to know the difference.
Your legal status as an immigrant in the United States is determined by the Department of Homeland Security (DHS) and the Department of State. DHS works through USCIS (United States Citizen Immigration Services) and the Department of State through the Bureau of Consular Affairs (Consulates and Embassies outside the U.S.)
An undocumented immigrant is any person that does not have a valid legal status emitted by any of these entities to live in the United States.
Not being able to show a document such as a visa or any permit that justifies your presence in the U.S. might put you in this category.
Any person failing to comply with the requirements and conditions of their immigration status is considered an illegal immigrant in the United States.
An example of an illegal immigrant is someone that could have been documented and authorized by USCIS or the Dept. of State, but their migration status is no longer valid. In other words, they are overstaying, accumulating unlawful presence in the United States.
So, are both the same?
For migratory purposes, yes, they are the same. An illegal immigrant and an undocumented immigrant are considered unauthorized immigrants or aliens since they are foreigners (not United States citizens).
Both are individuals who have either illegally entered the United States (without inspection) or legally entered it (with valid nonimmigrant visas), but their visas have expired.
If your visa or permit has expired and you are unsure where you are in your immigration process, you can clarify your status here (Link to the article How to Check my immigration status). Suppose you initiated a process with USCIS (United States Citizen Immigration Services) or CBP (Customs and Border Protection). In that case, you could use these links to track the status of your application, request, or petition.
