Quick Summary: The A-Number
| Question | Answer |
|---|---|
| What does A-Number stand for? | Alien Registration Number |
| Who issues it? | USCIS (U.S. Citizenship and Immigration Services) |
| Format? | Letter “A” followed by 8 or 9 digits (example: A012345678) |
| Who receives one? | LPRs, temporary visa holders in immigration processes, refugees, asylees |
| Do tourists get an A-Number? | Generally no, unless they have had immigration contact |
| Where to find it? | Front of green card, EAD card, USCIS I-797 notices |
| Does it change? | No — it is a permanent lifetime identifier |
| Is it the same as a Social Security Number? | No — they are completely separate numbers |
The U.S. Alien Registration Number, commonly abbreviated as an A-Number, is a unique identifier assigned to non-citizens by the United States Citizenship and Immigration Services (“USCIS”). This A-Number begins with the letter “A” followed by 8 or 9 numbers (such as A012345678). It is used to track individuals throughout their interactions with U.S. immigration authorities.
Who Has a U.S. Alien Registration Number?
Anyone who is not a U.S. citizen but resides in the United States may be assigned an Alien Registration Number. This includes
- Lawful Permanent Residents (“Green Card Holders),
- Individuals on temporary visas,
- Refugees, and
- Asylum seekers.
Even individuals who are in the U.S. without legal authorization may have an A-Number if they have had interactions with immigration authorities or if they are in proceedings to determine their immigration status.
What is the U.S. Alien Registration Number it used for?
- Identification: The primary purpose of the U.S. Alien Registration Number is to uniquely identify non-citizens in various interactions with U.S. government agencies, particularly those related to immigration and residency.
- Immigration Proceedings: A-Numbers are used extensively in immigration proceedings, including applications for green cards, asylum, and citizenship. They help immigration officials track individuals’ histories, applications, and statuses within the complex immigration system.
- Employment Authorization: Non-citizens who are authorized to work in the United States typically need to provide their Alien Registration Numbers to their employers for verification purposes, although the A-Number is not, on its own, evidence of work authorization.
- Taxation: A-Numbers may also be used for tax purposes, particularly for non-citizens who are required to file U.S. tax returns. This helps the Internal Revenue Service track tax liabilities and contributions.
- Law Enforcement: In some cases, law enforcement agencies may use A-Numbers to identify and track individuals who are involved in legal proceedings or criminal activities.
How to Find Your U.S. Alien Registration Number
If you are unsure whether you have a U.S. Alien Registration Number or need to locate it, there are several ways to do so:
- Immigration Documents: Your Alien Registration Number may be listed on various immigration documents, such as your green card, employment authorization card (EAD), or notices from USCIS.
- Correspondence from USCIS: Any official correspondence you have received from USCIS regarding your immigration status or applications will likely include your Alien Registration Number.
- Contact USCIS: If you still can’t find your A-Number, you can contact USCIS directly for assistance. Be prepared to provide personal information to verify your identity.
Alien Registration Number vs. USCIS Number
Many people as what is the difference between a USCIS number and an alien registration number, they serve different purposes:
| Feature | Alien Registration Number (A-Number) | USCIS Online Account Number |
| Who assigns it? | USCIS or DHS | USCIS (only if you create an online account) |
| Format | Begins with “A” + 8–9 digits (e.g., A012345678) | Numbers only, usually 12 digits |
| When issued? | When applying for certain immigration benefits (green card, asylum, deportation proceedings) | When you create a myUSCIS online account or file certain forms online |
| Permanent? | Yes, stays the same for life | No, only tied to your USCIS online account |
| Purpose | Immigration ID number used to track your case history across all applications | Login/account number used to access your USCIS online profile |
| Where to find it? | Green Card, Employment Authorization Document (EAD), USCIS notices (Form I-797) | USCIS online account profile page, online filing receipts |
Why the Alien Registration Number Matters
The A-Number is essential for navigating U.S. immigration law, from applying for immigration benefits to working legally in the U.S. and ensuring your records are tracked correctly.
The U.S. Alien Registration Number plays a vital role in the immigration process for non-citizens residing in the United States. From identification to immigration proceedings and beyond, this unique identifier is essential for navigating the complex legal and administrative landscape of U.S. immigration law. Understanding its significance can help individuals better manage their immigration statuses and interactions with government agencies.
The 5 Main Uses of an A-Number
| Purpose | Details |
|---|---|
| Identification | Unique identifier for all non-citizen interactions with U.S. government agencies |
| Immigration filings | Required for green card application (I-485), asylum, naturalization (N-400) and other USCIS forms |
| Work authorization verification | Employers may request the A-Number for verification; the number itself is not proof of work authorization |
| Tax purposes | IRS uses the A-Number to track tax obligations for non-citizens required to file U.S. returns |
| Law enforcement | May be used by law enforcement agencies to identify individuals in legal proceedings |
Frequently Asked Questions
What is an alien registration number (A-Number)?
An A-Number (Alien Registration Number) is a unique identification number assigned by USCIS to non-U.S. citizens. It begins with the letter “A” followed by 8 or 9 digits, for example A012345678. This number is permanent and does not change throughout the holder’s lifetime. It is used to track immigration records across the entire U.S. immigration system.
How is an A-Number different from a Social Security Number?
An A-Number and a Social Security Number (SSN) are entirely different numbers serving different purposes. The A-Number is assigned by USCIS to track immigration records, while the SSN is assigned by the Social Security Administration (SSA) to track earnings and Social Security contributions. Not all A-Number holders have an SSN and not all SSN holders have an A-Number. Only individuals authorized to work lawfully in the United States are eligible for an SSN.
Where can I find my A-Number?
Your A-Number can be found on your green card (front of card below your name), your EAD employment authorization card (labeled USCIS#), any I-797 Notice of Action from USCIS, or any official correspondence from USCIS related to your immigration file. If you cannot locate it, contact USCIS directly at 1-800-375-5283 or check your myUSCIS online account.
Does a Vietnamese national who just received a CR-1 visa have an A-Number?
Yes. When a Vietnamese national enters the United States on a CR-1 or IR-1 immigrant visa and becomes a Lawful Permanent Resident, USCIS assigns a unique A-Number. This number will appear on the green card mailed to the U.S. address after entry. The A-Number stays with the person for life, including if they later naturalize and become a U.S. citizen.
Do I need my A-Number when filing Form N-400 for naturalization?
Yes. Form N-400 (Application for Naturalization) requires your A-Number so USCIS can access your full immigration history during the adjudication process. The A-Number is also required on many other USCIS forms including I-485 (adjustment of status), I-90 (green card renewal) and a wide range of other immigration applications.
If you have questions about U.S. visas or immigration matters, contact us at info@enterlinepartners.com and speak with a U.S. immigration attorney in Ho Chi Minh City, Manila and Taipei.
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