F-1 students do not have an Alien Registration Number when they arrive in the United States or while they are simply enrolled in school. The A-Number is tied to immigration processes aimed at permanent residency or enforcement, and a typical F-1 student at entry falls into neither category. That changes for many students later on, most often when they file for work authorization through Optional Practical Training and USCIS opens a file in their name.
What an A-Number Is
An Alien Registration Number, also written A-Number or A#, is a unique seven- to nine-digit identifier that the Department of Homeland Security assigns to a non-citizen.1U.S. Citizenship and Immigration Services. A-Number/Alien Registration Number/Alien Number It always begins with the letter “A” followed by the digits, like A012345678. USCIS uses it to build and track a person’s immigration file (the A-File), which becomes the permanent record of every interaction that person has with the immigration system.
You will see the A-Number printed on documents like the Permanent Resident Card and the Employment Authorization Document. One detail catches many F-1 students off guard: USCIS defines the “USCIS Number” on these cards as the same identifier, cross-referenced directly to “Alien Registration Number.”2U.S. Citizenship and Immigration Services. USCIS Number – Definition So if you have an EAD with a nine-digit “USCIS#” on the front, that is your A-Number.
Why F-1 Status Doesn’t Come With One
F-1 is a nonimmigrant classification for people entering the country temporarily to study at an accredited academic institution or language training program.3U.S. Citizenship and Immigration Services. Chapter 8 – Change of Status, Extension of Stay, and Length of Stay Your I-94 record shows “D/S” (duration of status) rather than a fixed departure date, meaning you can remain as long as you stay enrolled and compliant.4U.S. Citizenship and Immigration Services. Form I-94, Arrival/Departure Record, Information for Completing USCIS Forms
Because A-Numbers exist to track permanent-residency and enforcement cases, USCIS has no reason to assign one at entry. You arrive with a passport, an F-1 visa stamp, and a Form I-20 from your school. None of those documents carry an A-Number.
When an F-1 Student Actually Gets One
Several situations cause USCIS to open a file and assign an A-Number to someone who started in F-1 status.
Filing for OPT or STEM OPT
This is where most F-1 students first encounter the A-Number. When you file Form I-765 for Optional Practical Training (or a STEM OPT extension), USCIS opens a file to process the application.5Study in the States. F-1 Optional Practical Training (OPT) The number printed as “USCIS#” on the resulting EAD is, by USCIS’s own definition, an Alien Registration Number.2U.S. Citizenship and Immigration Services. USCIS Number – Definition
This surprises a lot of students. You didn’t apply for a Green Card. You didn’t do anything “immigrant.” But the administrative machinery still created a permanent record and gave you an A-Number. Write it down and keep it. Future immigration forms will ask for it.
Applying for a Green Card
An F-1 student who files Form I-485 to become a lawful permanent resident receives an A-Number as part of that process. This is the more intuitive case, since adjustment of status is exactly the kind of immigrant benefit A-Numbers exist to track.6U.S. Citizenship and Immigration Services. Visa Availability and Priority Dates
Severe Economic Hardship Work Authorization
F-1 students facing unforeseen financial difficulty can apply for off-campus employment authorization based on severe economic hardship, which also requires Form I-765.7eCFR. 8 CFR 214.2 Same logic as OPT: if you don’t already have an A-Number, USCIS assigns one when it processes the application.
Removal Proceedings
If an F-1 student falls out of status and ends up in removal proceedings, USCIS or the immigration court assigns an A-Number to manage the case. A student can fall out of status by dropping below full-time enrollment, working without authorization, or failing to maintain a valid I-20. The A-Number follows that person through the entire enforcement process.
The Numbers You Do Have as an F-1 Student
Before an A-Number enters the picture, F-1 students carry a different set of identifiers.
Your SEVIS ID is printed at the top of your Form I-20 and follows the format “N” plus nine digits, like N000123456.8Study in the States. Students and the Form I-20 It tracks your student record within the Student and Exchange Visitor Information System. It is not an A-Number and is not interchangeable with one.
Your I-94 admission number proves your lawful entry. Since 2013, most I-94 records are created electronically, and you can retrieve yours through the CBP website.9Department of Homeland Security, U.S. Customs and Border Protection. I-94/I-95 Website Travel Record for U.S. Visitors
If you’re authorized to work, you’ll also have a Social Security Number; students receiving non-wage income like scholarships or investment earnings without work authorization use an ITIN instead.10Study in the States. Obtaining a Social Security Number Neither of those relates to an A-Number.
What to Write When a Form Asks for an A-Number You Don’t Have
This is where most F-1 students get stuck. A form asks for an Alien Registration Number and you’ve never had one. The answer depends on the form.
On Form I-765, if you’ve never been in removal proceedings and haven’t filed for a benefit that would have generated an A-Number, write “N/A” or leave the field blank as the form instructions direct. USCIS will assign one during processing.
On Form I-9, the employment eligibility form every new hire completes, F-1 students working under OPT who select “An alien authorized to work” must provide either their A-Number/USCIS Number or their I-94 admission number, along with their passport number and country of issuance.11Study in the States. USCIS Explains How to Complete Form I-9 If your EAD hasn’t arrived or you don’t know your A-Number yet, the I-94 admission number is the fallback.
How to Find Your A-Number if You Already Have One
If you were assigned an A-Number and can’t remember it, check the obvious places first:
- The front of your EAD card, in the field labeled “USCIS#.”
- Any USCIS notice (approval, receipt, or Request for Evidence), where the A-Number is printed near the top.
- Your USCIS online account case details, if you filed electronically.
If none of those work, you can request your immigration records through a Freedom of Information Act or Privacy Act request. As of January 2026, USCIS requires these requests to be submitted online at first.uscis.gov after creating a USCIS account, and the agency recommends requesting only the specific documents you need rather than your entire A-File.12U.S. Citizenship and Immigration Services. Request Records through the Freedom of Information Act or Privacy Act
Two Things People Get Wrong
Having an A-Number doesn’t mean you’re on a Green Card path. The number is an administrative tracking tool. Plenty of F-1 students get one through OPT, complete their training, and return home.
Switching to H-1B doesn’t generate a new A-Number on its own, because H-1B is still a nonimmigrant classification. If an employer later files an immigrant petition (Form I-140) for you, that process will assign an A-Number if you don’t already have one. Many former F-1 students already do, thanks to OPT.
And keep the two “N” and “A” identifiers straight. Your SEVIS ID starts with “N” and tracks your student record through SEVP. Your A-Number starts with “A” and tracks your immigration file at USCIS. Different systems, different documents, not interchangeable on any form.