Your USCIS A-Number appears on nearly every immigration document you receive: the front of your green card and work permit (labeled “USCIS#”), the top of any Form I-797C notice from USCIS, your immigrant visa foil (labeled “Registration Number”), and your Certificate of Naturalization or Citizenship. Knowing where to find your USCIS A-Number on your documents matters because the label changes from one document to the next, and the number sits next to other codes that are easy to grab by mistake.
On Your Green Card
The Permanent Resident Card (Form I-551) is the easiest place to look. On cards issued after May 10, 2010, the number appears on the front labeled “USCIS#” and runs nine digits.1U.S. Citizenship and Immigration Services. USCIS Number Older versions may label the same field “A#” and show only seven or eight digits. It sits near your biographical information on the front,2U.S. Citizenship and Immigration Services. 13.1 List A Documents That Establish Identity and Employment Authorization and on some versions it is repeated on the back.
On Your Work Permit
The Employment Authorization Document (Form I-766) displays the A-Number on the front, again labeled “USCIS#,” alongside your photo, name, date of birth, and card expiration.2U.S. Citizenship and Immigration Services. 13.1 List A Documents That Establish Identity and Employment Authorization If you hold both a green card and an EAD, the number on each should match. Copy it directly from the card when filling out a form; don’t rely on memory.
On USCIS Notices (Form I-797C)
If your card hasn’t arrived yet, or you can’t find it, check any Notice of Action USCIS has sent you. The A-Number appears near the top of the page in a field labeled “USCIS#” or “A-Number,” grouped with your name.3U.S. Citizenship and Immigration Services. Form I-797C, Notice of Action For readers between applications or waiting on a card in the mail, the I-797C is the most reliable backup.
Don’t Grab the Receipt Number by Mistake
The same notice shows a receipt number, and the two are often confused. A receipt number is 13 characters: three letters (like IOE, EAC, or LIN) followed by 10 digits.4U.S. Citizenship and Immigration Services. Receipt Number It tracks a single application, and you get a new one every time you file. Your A-Number tracks you and never changes. On the form you’re filling out, look for the label “A#” or “USCIS#” specifically; entering the receipt number in that field can cause delays or a rejection.
On Your Immigrant Visa and Fee Handout
If you entered the United States through consular processing, your A-Number is printed on the immigrant visa foil placed inside your passport. On the visa it’s labeled “Registration Number,” not “A-Number” or “USCIS#.”5U.S. Citizenship and Immigration Services. Immigrant Fee Payment: Tips on Finding Your A-Number and DOS Case ID CBP may also annotate it near the entry stamp when you arrive.6U.S. Embassy & Consulates in Brazil. Immigrant Visas: Know Before You Go
Also check the Immigrant Fee Handout you received at your consular interview. Your A-Number and Department of State Case ID appear in the top right corner.5U.S. Citizenship and Immigration Services. Immigrant Fee Payment: Tips on Finding Your A-Number and DOS Case ID Both numbers are needed to pay the USCIS Immigrant Fee online, which has to be paid before USCIS will produce your green card, so hang onto that sheet.
The A-Number Looks Different From the DOS Case ID
An A-Number starts with the letter “A” followed by eight or nine digits (for example, A012345678). A DOS Case ID has a different shape: typically three letters followed by nine or ten digits (for example, RDJ0123456789). Diversity Visa lottery winners get another format: four digits, two letters, then five more digits.6U.S. Embassy & Consulates in Brazil. Immigrant Visas: Know Before You Go The fee portal asks for both, and putting the wrong one in the wrong field will block your payment.
On Your Certificate of Naturalization or Citizenship
Naturalized citizens can find their A-Number on Form N-550 (Certificate of Naturalization) or Form N-570 (Certificate of Citizenship). Watch out: the certificate number and the A-Number are two different things. The certificate number is an alphanumeric code that usually appears in the upper right corner. The A-Number is the familiar “A” plus digits you’ve had since your first immigration filing. Family-based petitions like Form I-130 ask for your A-Number even after naturalization, so keep the certificate accessible.
In Your USCIS Online Account
If you have a myUSCIS account at myaccount.uscis.gov, your A-Number may appear in your case information once you’ve linked a pending or completed application.7U.S. Citizenship and Immigration Services. How Do I Get a New Online Access Code? Linking a case requires the receipt number from an I-797C notice, so this works as a complement to your paper documents rather than a substitute. If you filed your last application online, your case details, A-Number included, should already show on your dashboard once the case is receipted.
If You’ve Lost Every Document
When nothing is available, you can request your immigration records through a Freedom of Information Act or Privacy Act request. As of January 22, 2026, USCIS requires these requests to be submitted online at first.uscis.gov after creating a USCIS account.8U.S. Citizenship and Immigration Services. Request Records through the Freedom of Information Act or Privacy Act The older paper Form G-639 is no longer the standard method, and online submission is generally the only accepted channel.9National Archives. Using FOIA to Access Immigration Records
If you can’t file electronically (for example, if you are incarcerated), the DHS FOIA Public Liaison may arrange an alternate method. They can be reached at FOIAPAQuestions@uscis.dhs.gov or 1-800-375-5283.9National Archives. Using FOIA to Access Immigration Records Standard records requests generally carry no fee, but USCIS warns that large file requests take significantly longer than requests for a specific document. Give yourself time if you need the number before a filing deadline.
What If a Form Asks and You Don’t Have One?
Not every noncitizen has an A-Number. USCIS assigns one to people who interact with the immigration system in a way that requires long-term tracking: green card applicants, EAD holders, asylum seekers, DACA and TPS recipients, and people in removal proceedings. Short-term visitors on tourist visas, standard student visas without work authorization, and Visa Waiver Program travelers generally do not get one.10U.S. Citizenship and Immigration Services. A-Number/Alien Registration Number/Alien Number If you’ve never filed an immigration application or been in deportation proceedings, you likely don’t have one yet, and a form field asking for it can be left blank.
Once you’re assigned an A-Number, it’s permanent. It doesn’t change when you renew your green card, adjust status, or file additional applications, and it follows you through naturalization.