If you've arrived in the U.S. without a Social Security Number, you've probably heard about both an ITIN and an SSN. They look similar — both are 9-digit numbers — but they serve very different purposes, issued by different agencies, to different groups of people.
Quick Answer
An SSN (Social Security Number) is for U.S. citizens and people authorized to work in the U.S. An ITIN (Individual Taxpayer Identification Number) is for people who have a U.S. tax obligation but are not eligible for an SSN — mainly undocumented immigrants and nonresident aliens. Both let you file taxes. Only the SSN authorizes work and federal benefits.
What Each Number Is
Social Security Number (SSN)
The Social Security Number is issued by the Social Security Administration (SSA). It is the primary identification number used in the U.S. for employment, federal benefits, credit, and most government services. To get an SSN you must be a U.S. citizen, a lawful permanent resident (green card holder), or have a valid work authorization visa (such as an H-1B, TN, or EAD).
Individual Taxpayer Identification Number (ITIN)
The ITIN is issued by the IRS — not the Social Security Administration. It exists solely so that people with a U.S. tax obligation can file a tax return even if they are not eligible for an SSN. This includes undocumented immigrants, certain nonresident aliens, and foreign nationals earning U.S. income. An ITIN does not change your immigration status, authorize employment, or make you eligible for Social Security benefits.
Side-by-Side Comparison
| Category | SSN | ITIN |
|---|---|---|
| Issued by | Social Security Administration | IRS |
| Who qualifies | U.S. citizens, permanent residents, authorized workers | People with U.S. tax obligation but no SSN eligibility |
| Format | XXX-XX-XXXX | 9XX-XX-XXXX (always starts with 9) |
| File federal taxes | ✓ Yes | ✓ Yes |
| Open a bank account | ✓ Yes | ✓ Yes (most major banks) |
| Apply for credit cards | ✓ Yes | ✓ Yes (Chase, Amex, Capital One) |
| Buy or rent a home | ✓ Yes | ✓ Yes (ITIN mortgages available) |
| Apply for a driver's license | ✓ Yes (all states) | ✓ Yes (19+ states accept ITIN) |
| Invest in stocks / ETFs | ✓ Yes | ✓ Yes (some brokers accept ITIN) |
| Authorize legal employment | ✓ Yes | ✗ No |
| Collect Social Security benefits | ✓ Yes (if work credits earned) | ✗ No |
| Federal student aid (FAFSA) | ✓ Yes (eligible students) | ✗ No (state aid may be available) |
| Expires | ✗ No (permanent) | ✓ Yes (if unused 3+ years) |
What You Can Do With an ITIN
Despite the limitations above, an ITIN opens more doors than most people realize. Here is what's possible:
- File federal and state taxes — and potentially receive refunds, including the Child Tax Credit in some cases
- Open a checking or savings account at major banks like Chase, Bank of America, Citibank, and Wells Fargo
- Apply for credit cards — Chase, American Express, and Capital One all accept ITIN on applications (see the full credit card guide)
- Build a U.S. credit history — your ITIN activity is tracked by Experian, Equifax, and TransUnion
- Buy or rent a home — ITIN mortgages are available through specialized lenders
- Get a driver's license — over 19 states accept ITIN as part of their license application (see the full state list)
- Start a business or LLC — you can obtain an EIN using your ITIN
- Send money internationally and use services like remittances
- Get car insurance and other financial products without an SSN
More than you think
Many ITIN holders don't realize how much of the U.S. financial system is accessible. Banks have quietly accepted ITIN for years. Credit card issuers like Chase and Amex allow ITIN in their online applications. The main limitations are employment authorization and federal benefit programs — not everyday financial life.
What an ITIN Cannot Do
It's equally important to know what an ITIN does not give you:
- Work authorization — employers use Form I-9 to verify work eligibility, and an ITIN is not an acceptable I-9 document
- Social Security benefits — you cannot claim retirement, disability, or survivor benefits using an ITIN (even if taxes were paid under a shared or borrowed SSN)
- Federal student financial aid — FAFSA requires an SSN; however, some states (like California) have their own aid programs that accept ITIN
- Medicare or Medicaid enrollment — these federal programs require an SSN
- A path to immigration status — having an ITIN does not change your immigration status or create any legal status in the U.S.
ITIN is a tax number only
The IRS issues ITINs strictly for tax purposes. Applying for an ITIN does not put you in any immigration database, and the IRS is legally prohibited from sharing your tax information with immigration agencies. However, an ITIN alone has no immigration benefit or protection. For immigration-related questions, consult a qualified immigration attorney.
Switching From an ITIN to an SSN
If your immigration status changes — for example, you receive a work permit, a visa that allows employment, or a green card — you become eligible to apply for a Social Security Number. When that happens:
- Apply for your SSN at your local Social Security Administration office with your new immigration documents
- Notify the IRS by writing to the IRS with both your ITIN and new SSN so your tax records can be merged
- Notify the credit bureaus — contact Experian, Equifax, and TransUnion and request that your credit history built under your ITIN be linked to your new SSN. This is important: your credit history does not transfer automatically
- Update your bank accounts — notify your banks of your new SSN if they require it
Credit History Transfer
Credit bureaus can link your ITIN-based credit history to your new SSN when you request it directly. This means the credit you built with your ITIN — your payment history, account age, and credit limits — may not be lost when you get an SSN. Contact each bureau separately and ask about their ITIN-to-SSN credit record linking process. Policies and results may vary.
How to Get an ITIN
If you need an ITIN, you apply using IRS Form W-7 along with a federal tax return and proof of identity and foreign status. The process is free and takes 7–11 weeks by mail. See the full guide: