Basic Immigration Concepts

An “A-Number” is a unique identification number that immigrants must provide on their immigration forms and documents. It allows the government to track an individual’s immigration history and status. An A-Number is similar to a Social Security number for U.S. citizens, but it is specific to non-citizens and their immigration process. It will always be tied to an immigrant’s A-File, and they are usually nine digits long. However, some older A-Numbers may be seven or eight digits long.

An “A-File” is an immigrant’s official immigration record. Any non-citizen who has had an interaction with a U.S. immigration authority will have an A-File. A-Files are kept by the following three agencies: United States Citizenship and Immigration Services (USCIS), Customs and Border Protection (CBP), and Immigration and Customs Enforcement (ICE).

Anyone who has ever applied for an immigration benefit in the United States or entered the United States illegally and been detained will have an A-File.

A-numbers can be found on immigration documents issued by USCIS, like green cards, work permits, visas, and notices. They can also be found on documents issued by ICE or CBP, like a Notice to Appear (NTA).

United States Citizenship and Immigration Services (USCIS) is the federal government agency that oversees lawful immigration to the United States. This agency is responsible for processing immigration and naturalization applications. USCIS also establishes policies regarding immigration services.

Immigration and Customs Enforcement (ICE) is a federal law enforcement agency responsible for enforcing immigration laws in the United States.

Customs and Border Protection (CBP) is the federal law enforcement agency responsible for protecting the United States’ borders by enforcing immigration law. CBP also inspects travelers at ports of entry.

A Notice to Appear (NTA) is the official immigration document that initiates removal, or deportation, proceedings for an individual in immigration court. This document orders a non-citizen to appear at their scheduled hearing before an immigration judge to determine whether they can remain lawfully in the United States. An NTA can be issued by ICE or by USCIS.