An A-number (Alien Registration Number, also called an alien number, A# or, on newer cards, the “USCIS#”) is the unique number the Department of Homeland Security assigns to a noncitizen’s immigration file. It is usually written as the letter A followed by 8 or 9 digits, such as A012345678. You can find it on your green card, your work permit (EAD), most USCIS notices, your immigrant visa stamp and any immigration court papers. It is not the same as your USCIS online account number, a receipt number or your I-94 number. This guide explains where to look, how to write it on forms, and what to do if you can’t find it.
What Is an A-Number?
USCIS defines the A-number as a unique seven-, eight- or nine-digit number that DHS assigns to a noncitizen (USCIS glossary). It identifies your “A-file,” the government’s record of your immigration history. The same number follows you for life, through every application, card and court case, and it stays in your file even after you become a U.S. citizen.
Not everyone has one. Many people on temporary visas, such as visitors and students, never receive an A-number. It is generally created when you apply for or receive certain benefits, for example a green card or a work permit, or when DHS opens a file on you, for example in removal (deportation) proceedings.
Where to Find Your A-Number
- Green card (Form I-551): on cards issued after May 10, 2010, it is the 9-digit USCIS# on the front of the card (USCIS glossary: USCIS Number). Add the letter A in front when a form asks for your A-number.
- Work permit (EAD, Form I-766): the A-number is usually printed as the USCIS# on the front of the card.
- USCIS notices (Form I-797): receipt, appointment and approval notices usually show your A-number near the top if you have one.
- Immigrant visa: the visa stamp in your passport lists it as the Registration Number. It is also at the top of the Immigrant Data Summary and on the USCIS Immigrant Fee handout you received from the consulate (USCIS: finding your A-number and DOS Case ID).
- Immigration court papers: the Notice to Appear, hearing notices and judge’s orders all show the A-number. The immigration court system says the number is printed on all DHS and immigration court correspondence (EOIR).
- Your own copies: copies of past applications you or a lawyer filed, and letters from ICE or CBP, often list it too.
How to Write Your A-Number on Forms
USCIS forms have nine boxes for the A-number. If yours has fewer than nine digits, add zeros right after the “A” and before the first digit until there are nine. For example, A12345678 becomes A012345678, and A1234567 becomes A001234567. The N-400 instructions and USCIS’s immigrant fee guidance both give this rule. Some systems, such as the immigration court hotline, ask for the nine digits without the letter A.
Use the same A-number on every form. If you have ever been given more than one, list all of them where the form asks, and tell your attorney; two files can mean records that need to be combined.
A-Number vs Other Immigration Numbers
People often mix up the A-number with other numbers on their papers. Here is how to tell them apart:
| Number | What it looks like | What it identifies | Where to find it |
|---|---|---|---|
| A-number (USCIS#) | A + 8 or 9 digits | You, for life (your immigration file) | Green card, EAD, USCIS notices, immigrant visa, court papers |
| Receipt number | 13 characters: 3 letters (such as IOE, EAC, MSC, LIN) + 10 numbers | One application or petition | Form I-797 receipt and approval notices |
| USCIS online account number | A number with no “A” | Your USCIS online account | Your online account profile or the USCIS Account Access Notice |
| I-94 number | 11 characters | One entry into the U.S. | CBP I-94 website |
| DOS Case ID | 3 letters + 9 or 10 numbers | Your case at the National Visa Center or consulate | State Department letters, Immigrant Data Summary |
USCIS online account number vs A-number
The USCIS online account number is not your A-number. According to USCIS form instructions, you have one only if you filed something with a receipt number that begins with “IOE,” either online or on paper. If you filed online, it is in your account profile; if you mailed a form, it appears on your Account Access Notice. Older notices may call it the “USCIS ELIS Account Number.” If you have no IOE receipt, leave the online account number box blank rather than writing your A-number there.
Receipt number vs A-number
A receipt number tracks one application, so you get a new one each time you file. You use it to check that case on USCIS Case Status Online. Your A-number stays the same across all of your cases.
Checking an Immigration Court Case With Your A-Number
If you or a family member has a case in immigration court, the A-number is the key to checking it. As of November 2026, you can:
- Use the EOIR Automated Case Information website, entering the A-number and nationality.
- Call the toll-free hotline at 1-800-898-7180, available 24 hours a day in English and Spanish. Enter the 9 digits without the letter A; if the number has 8 digits, enter a 0 first.
These tools show the next hearing date and location and the judge’s decision, but they do not cover bond hearings; for bond information, contact the court. If a relative has been detained, the A-number also helps you find them through ICE’s detainee locator. See our immigration bond and ICE detention page and our deportation defense page, and, in Spanish, qué hacer si ICE detiene a un familiar.
The Alien Registration Requirement
The name “alien registration number” comes from the federal registration law, which requires most noncitizens age 14 or older who stay in the U.S. 30 days or longer to register and be fingerprinted. Most people with a visa, I-94, work permit or green card are already registered. Since April 2025, people who have never registered can use Form G-325R. As of November 2026, USCIS says Form G-325R is still available after a final rule published June 29, 2026 (USCIS: Alien Registration Requirement). Registration is not an immigration status and carries real risks for people without status, so talk to an attorney first. Our Spanish guide to Form G-325R covers who must register.
What If You Don’t Know Your A-Number?
- Check every card and notice listed above, including old ones, and copies of past applications.
- Ask the lawyer or representative who filed for you before; they should have it in their file.
- Request your records from USCIS through a Freedom of Information Act (FOIA) request. You can file online or with Form G-639, and you can leave the A-number box blank if you don’t know it; USCIS searches using your name, date and place of birth. A FOIA response also shows what is in your file, which is useful before filing anything new.
- If you are unsure whether you ever had one, leave the field blank or write “None” as the form’s instructions direct. Do not guess or borrow a family member’s number.
Keep Your A-Number Private
Treat your A-number like a Social Security number. Don’t post photos of your green card, work permit or notices on social media, and don’t give the number to anyone who calls or messages you claiming to be from USCIS or the immigration court. EOIR has warned that scammers spoof its phone number. Share your A-number only on official forms, with government agencies, with your employer for Form I-9 when required, and with your attorney.
Common Questions About A-Numbers
Is the USCIS number the same as the A-number?
Yes. The “USCIS#” on a green card or work permit is your A-number shown as nine digits without the letter A. It is different from the USCIS online account number.
Does my A-number change when I get a green card or become a citizen?
No. Your A-number stays the same through every application, including a green card renewal with Form I-90 and naturalization. After you become a citizen you no longer need it for most purposes, but it remains the number on your file. See permanent resident vs U.S. citizen.
Is the green card “Category” code part of the A-number?
No. The category (such as IR6 or CR1) shows how you got your green card. See our list of green card category codes and our guide to the IR6 category.
Can I have an A-number without a green card?
Yes. People with work permits, pending applications (such as a Form I-485 adjustment of status application), asylum cases or immigration court cases often have an A-number without being permanent residents. Having an A-number does not by itself give you any status.
Consultations
If you can’t find your A-number, think you have more than one, or need to check a court case, our attorneys can review your documents. A consultation is a 30-minute appointment at our Norcross office or online, held in English: $175 with Bhavya Chaudhary, or $150 with Ashish Ranjan or Rachana J. Vijayathilakan. Bring your cards, notices and any court papers.
- Book with Bhavya Chaudhary ($175)
- Book with Ashish Ranjan ($150)
- Book with Rachana J. Vijayathilakan ($150)
Or call 678-292-6111. Learn more about our family immigration and naturalization services.
This page provides general information and is not legal advice. Every case is different; speak with an attorney about your situation.
