Alien Registration Number FAQ

Updated on September 18, 2020

Question: What is an “Alien Registration Number”?

An alien registration number is a number assigned by the United States Citizenship and Immigration Services (USCIS) to you as a non-U.S. citizen. It is made up of seven, eight or nine digits and is unique to you. It is also called “A-Number”, “A#”, “Alien Number”, “Registration Number”, “USCIS Number”, “USCIS Alien Number”, “USCIS#”, “INS Number”, “INS Registration No.”, “INS#”.

Question: Who will get an Alien Registration Number?

   Learn more about I-797 Notice of Action in our article USCIS I-797 Notice of Action Explained.

At DYgreencard, we may help you handle many types of applications, like I-485 adjustment of status to apply for green card, I-130 immigrant petition for spouse, parent, child, or sibling, I-129F petition/K-1 visa for fiancé(e), I-751 petition to remove conditions on green card, I-765 application for employment authorization, I-90 application to renew green card, N-400 application for naturalization, I-131 application for reentry permit or advance parole or refugee travel document, and more. All you need to do is just answer a few simple questions online and upload supporting documents to our platform. Then we take care of the rest. The entire application package will be carefully reviewed by a professional immigration attorney to ensure its final approval by USCIS. Learn more about what we can do for you.

Question: Where can I find my A-Number?

Actually, you may find the A-Number in various immigration-related documents if ever assigned one.

Find A-Number on green card

Because USCIS redesigned green card several times, green card has different versions.

Alien Registration Number on Green Card-1
Alien Registration Number on Green Card-1
Alien Registration Number on Green Card-2
Alien Registration Number on Green Card-2
Alien Registration Number on Green Card-3
Alien Registration Number on Green Card-3


Find A-Number on EAD

Alien Registration Number on EAD
Alien Registration Number on EAD


Find A-Number on I-797 Notice of Action

There are many versions of I-797 Notice of Action. Each type of application or petition has its own version. As a result, the location of A-Number varies.

Alien Registration Number on I-797 Notice of Action
Alien Registration Number on I-797 Notice of Action


Find A-Number on immigrant visa stamp

Alien Registration Number on Immigrant Visa Stamp
Alien Registration Number on Immigrant Visa Stamp


Find A-Number on certificate of naturalization

Alien Registration Number on Certificate of Naturalization
Alien Registration Number on Certificate of Naturalization


Find A-Number on certificate of citizenship

Alien Registation Number on Certificate of Citizenship
Alien Registation Number on Certificate of Citizenship


Question: Why Alien Registration Number is important?

Alien Registration Number is the number that identifies noncitizen’s official files for all immigration and naturalization records created or consolidated since April 1, 1944. Such files are called Alien File, or “A-File”. With an A-Number, USCIS may easily locate all immigration records that applicants ever have. As a practice of USCIS, one alien should have only one A-File or USCIS should combine all A-Files that the alien has into one A-File.  

Question: How to fill out in the application form if I never have or forgot an A-Number?

You may just leave it blank or type “N/A” if you never have one. If you forgot it, you may write down “Forgot”.

Question: How to fill out in the application form if my A-Number only has 7 or 8 digits?

Just add 0 in the beginning to make the number with 9 digits.

Question: Is it possible that one has two or more A-Number?

Yes. Even if you are not mandatory to provide all of them when filing application to USCIS, it is advisable to provide all A-Numbers so that USCIS may easily combine all immigration records identified by each A-Number to one A-File.

Question: Is an A-Number the same as a Social Security Number?

No. Although it also has nine digits and is unique to the holder, a Social security number is issued by the Social Security Administration and is used for tax and related purposes. Please see our article Social Security Numbers for Foreigners for more information about whether you as a non-citizen need to have one and, if so, how to request it.

Question: Is an A-Number the same as a USCIS Case Number?

No. USICS Case Number is also known as USCIS receipt number. It is a 13-digit number that begins with three letters followed by a series of 10 digits. You may always find an USCIS case number in an I-797 Notice of Action issued by USCIS when filing an immigration-related application to USCIS.

Question: Is an A-Number the same as a Green Card Number?

No. Green Card Number is a 13-digit number that is printed on a permanent resident card (“green card”). You may learn more about it in our article Where to Find Green Card Number?

Question: Is an A-Number the same as a Visa Number?

No. Visa Number is a red number located in the bottom right of a newer issued U.S. visa. You may learn more about it in our article Where to Find Visa Number?

Related Topics:

DYgreencard — for people who want the expertise of immigration lawyer, with a lower price.


(Copyright by DYgreencard.com. To copy or distribute any of its content must be marked with the sentence “copied or distributed from DYgreencard.com”.)