Alien Registration Number: What is an “A” Number and Where Can I Find it on My Green Card?

Alien Registration Number: What is an “A” Number and Where Can I Find it on My Green Card?

When you apply for a green card, United States Citizenship and Immigration Services (USCIS) will ask you to list your alien registration number—also known as your “A-Number”—on your petition or application form. You may also be asked to provide your USCIS number, which is different than your alien registration number.

In this article, you will find out:

  • What an alien registration number is
  • The types of A-Numbers
  • Where to find your A-Number
  • Your A-Number eligibility

We will also discuss what happens if you lose your alien number and the differences between your A-Number and your USCIS number. Understanding your A-Number will help you when filling out documents both before your legal entry into the United States and throughout the duration of your stay in the U.S.

What Is an Alien Registration Number?

An alien registration number (A-Number) is the identification number given to you by USCIS. It is a seven to nine-digit number that acts as your identification. Your alien registration number is used to keep track of documents and immigration files.

Your alien registration number is unique to you. Your A-Number is one you will keep for life and will use when filling out all immigration forms that you file in your lifetime. Alien numbers are only for those who are not United States citizens.

Alien Number Types

Most A-Numbers are nine digits, but there are certain types of A-Numbers that are less than nine digits long. If your A-Number is less than nine digits, place a zero (0) between the “A” and the starting digit to make your A-Number a complete nine digits.

Example: 1234567 would become A001234567.

Where Do I Find My Alien Registration Number?

A-Numbers are typically on all of your immigration documents. This can include your:

  • Initial notice that USCIS received your application
  • Approval notices
  • Immigrant visa card
  • Permanent resident green card
  • Almost all immigration documents

If you are wondering where to find the alien registration number on your green card, there are multiple places to find it. If searching for your permanent resident card alien number on your green card, your A-Number will be located on the front side and backside of the card. It may seem confusing, but your alien registration number on your green card is actually named under USCIS# on the physical card itself.

Close-Up View of an Example of a Permanent Resident Card

To find your A-Number on your immigrant visa, look beneath “Registration Number” on the top right of the visa stamp.

What Do I Use My Alien Registration Number For?

You may be wondering “What is my alien registration number actually used for?” Your A-Number functions similarly to a U.S. citizen and permanent resident’s social security number. It’s the number assigned specifically to you as a form of identification. Your alien registration number is also used by the government in many other ways, including:

  • Identifying the number of resident immigrants who are in the United States
  • Keeping and accessing your immigration records and other legal or illegal activities

The government may also use your alien registration number to track you down in case of an emergency.

At its most basic function, your A-Number is used as your main form of identification.

Am I Eligible for an A-Number?

Everyone who applies for a green card is eligible for an alien registration number. A-Numbers are necessary for all people who intend to or currently live permanently in the United States. Your eligibility is not determined by the type of green card you have (family, refugee, employment, etc.). If you are coming to the United States permanently, you will receive an A-Number.

Along with those who have immigrant visas, F-1 student visa holders are also given an alien registration number, even though they are not in the United States as green card holders nor applying for green cards. That being said, if you are an F-1 student visa holder and have questions about changing your status to an H1-B, contact us today.

Who Is Not Eligible for an Alien Number?

Temporary non-immigrant visa recipients are not given A-Numbers. The shorter-term stays in the United States do not require documents that ask for an A-Number. Again, the only exception is F-1 student visa holders.

When Am I Eligible for My Alien Registration Number?

The timeline for receiving your alien registration number is fairly quick. Most people get their alien number when they apply for a green card.

If you are applying for a green card under any of the following circumstances, you may acquire your alien registration number in other forms:

  • You are applying for a marriage green card while outside the United States
  • You are married to a U.S. citizen
  • You have worked under the Optional Practical Training program

If you are applying for a marriage green card from outside the U.S., you will get your alien number at your consular interview, which you will attend at your country’s U.S. Consulate. Note that if you are applying for a marriage green card while already in the United States, you will find your alien registration number in your receipt notice.

If you are already married to a United States citizen, you will get your alien number about a month (approximately 30 days) after filing your green card application form. If you have not yet started your green card process, you must first:

  • Petition for Form I-130, Petition for an Alien Relative
  • Once your Form I-130 is approved, you will need to apply for an immigrant visa (under a category for which you qualify)
  • You will then file your Form I-485, Adjustment of Status

If you have worked under the Optional Practical Training program, there is also another process. If you are already an F-1 visa holder (for students) and have work authorization, you most likely already have an alien number.

What Happens If You Lose Your Alien Number?

If by any chance you lose your physical green card or any other immigration documents, you will be able to access your A-Number through the Freedom of Information Act (FOIA) online system or by setting up an appointment with USCIS. If you have any questions about the process of accessing your A-Number or would like assistance, we can help you with any or all portions of the process.

Difference Between Alien Registration Number and Your USCIS Number

“Is a USCIS number the same as an alien number?” is a question we are often asked. Your alien registration number is different from your USCIS case number. However, the case number and USCIS number found on your green card differ.

Here is the confusing part: Your USCIS number on your green card is actually your alien number, whereas your USCIS case number for your applications is different.

Your USCIS case number is assigned to your application, which is different from your identification number.

To further break the difference down, each application you file through USCIS will have a USCIS case number. Your A-Number (possibly marked USCIS # on your green card, depending on your visa) is your identification number. Your alien number will stay constant between applications; each application number will be different.

You can tell the difference between your alien registration number and your USCIS case number by the number of digits.

  • Your A-Number has 7, 8, or 9 digits
  • Your USCIS case number has 3 letters followed by 10 numbers, totaling 13 characters


Do I Get an Alien Registration Number If I Am a DACA Recipient?

When you file Form I-821D for the first time, you may already have an A-Number. If you do not, you will be assigned one, but if you have had any interaction with USCIS, it is possible you already have an alien number. Be sure to check any paperwork or documentation sent by USCIS. If you are renewing your DACA status, you will use your A-Number to refile.

Does My Alien Registration Number Expire?

No, your alien registration number does not expire. However, it is important to point out that your immigration status can expire.

Is My Alien Number on My Green Card Also on My Passport?

Your alien number can be found on your immigration visa stamp.

If you applied for your green card while already inside the United States, you will probably not have a stamp on your passport, meaning you will not have your A-Number in your passport.

Contact an Immigration Attorney

If you have any questions about your alien registration number or the immigration process in general, please reach out to the experienced immigration and naturalization attorneys at Scott D. Pollock & Associates P.C. With over 30 years of practice, we have in-depth knowledge and experience in all topics of immigration law. We can keep you updated on immigration policy and when/where you may need your alien number. You can call us anytime at 312.444.1940 or fill out an online contact form today. We look forward to hearing from you!

We're looking forward to hearing from you!