SSN and ITIN: How to Apply for a US Taxpayer ID as a Newcomer

Every US tax return, payroll form and bank interest report needs a taxpayer identification number, so the SSN and ITIN question comes first for newcomers. The Social Security number (SSN) is issued by the Social Security Administration (SSA) to people admitted for permanent residence or work. The Individual Taxpayer Identification Number (ITIN) is a tax-only number issued by the IRS to people who must file, or be claimed on, a return but cannot get an SSN. Choosing the wrong one delays refunds, payroll and credits, and it affects your first-year return.

SSN and ITIN: which one do you need?

The IRS states that a nonresident alien with a US work visa qualifies for an SSN and does not need an ITIN. If the SSA application is pending, do not file Form W-7; you submit it only after SSA says you are ineligible and gives you a denial letter.

How to apply for an SSN

1. Check eligibility. SSA says some noncitizens can get a number if they work, or have a valid nonwork reason, and you need a visa status that supports it.
2. Gather originals. Typically your passport, visa, I-94 record, and for students the I-20 or DS-2019 with employment authorization papers (see our guide for students and scholars). SSA publishes document lists for noncitizens, international students and foreign workers.
3. Apply. If you are in the United States, SSA says you can start online and then visit a local office with your documents. Form SS-5 is the paper application.
4. Wait for the card. SSA says the card arrives by mail 5 to 10 business days after approval. The IRS Form 1040 instructions say about 2 weeks once SSA has all the evidence.
5. Give the number to your employer on Form W-4 (see withholding for newcomers) and keep the card in a safe place. Do not carry it daily.

An SSN also starts your Social Security earnings record, explained in our Social Security and Medicare guide. Use your SSN on your tax return even if your card says it is not valid for work. If you earlier used an ITIN, stop using it and write to the IRS asking that your records be combined under the SSN.

How to apply for an ITIN

1. Confirm a federal tax purpose. That means a required return, a refund claim, being a spouse or dependent for an allowable tax benefit, or another listed reason in the Form W-7 instructions. A return with all zero entries generally does not count.
2. Complete Form W-7 (December 2024 revision) and tick the reason box. Nonresident students and scholars also use the box that matches their treaty exception.
3. Attach the application to your tax return. First-time applications and renewals need a return unless one of five exceptions applies, such as third-party withholding on passive income, treaty claims or mortgage interest reporting.
4. Prove identity and foreign status. An original passport, or a copy certified by the issuing agency (including the US visa pages), is the only stand-alone document. Otherwise send at least two documents from the list of 13, with a photograph on at least one.
5. Submit through one of three routes. Mail to the IRS ITIN Operation in Austin, Texas; apply in person at a designated Taxpayer Assistance Center by appointment; or use an acceptance agent.
6. Wait for notice CP565, which shows your assigned number.

Acceptance agents (AAs) help prepare and submit the application but send original documents to the IRS. A certifying acceptance agent (CAA) can verify your original documents and return them immediately, which helps if you need your passport for travel. Both are available in the United States and abroad. Use only agents listed by the IRS and read our scam alerts.

Documents you need

• Passport (best single document) and US visa pages
• I-94 record and the date of entry into the United States
• Form I-20 or DS-2019 and a letter from your designated school official if you are a student not employed
• Proof of foreign status such as a national ID card with name, photograph, address, date of birth and expiration date
• For dependents: birth certificate, and proof of US residency if the passport lacks an entry date
• A signed return, if one is required with the application

Deadlines, renewals and penalties

• Apply on or before the return due date; if you need more time, request an extension.
• You must have an ITIN assigned to you, your spouse and your dependent by the due date (including extensions) to claim certain credits, such as the credit for other dependents. For 2025, the child tax credit also requires an SSN valid for employment.
• If you use an ITIN in the same calendar year you receive it, you cannot e-file; you may e-file in later years.
• An ITIN not used on a federal return for three consecutive tax years expires on December 31 of the third year, and ITINs issued before 2013 have already expired. Renew with Form W-7 and a return.
• Leaving off a required taxpayer ID can bring a $50 penalty per failure, according to Publication 519.

Country notes

Moving from India? Our India-to-US tax checklist puts the SSN step in order with banking, payroll and Indian account decisions.

Worked example: Rahul and Anjali, Naperville

Rahul arrives on an H-1B in February 2025 and receives an SSN. His wife Anjali arrives on an H-4 without an EAD. Both pass the substantial presence test for 2025 and elect to be taxed as US residents for the whole year, which allows a joint return. Anjali needs an ITIN as a spouse on that joint return. They complete Form W-7 for her, attach her passport (or a certified copy) and mail it with their joint Form 1040 to the ITIN Operation. They do not file electronically while the ITIN is pending. Anjali's ITIN is used on their 2026 return, and she gets an SSN later if she obtains work authorization.

Mistakes to avoid

• Filing Form W-7 while an SSA application is pending.
• Sending a photocopy of a passport that is not certified.
• Using an ITIN as proof of work authorization. It is not.
• Letting a dependent's ITIN expire before claiming a credit.
• Hiring an unlisted "agent" who keeps your original passport.

How we can help

Our firm in Aurora, Illinois prepares Form W-7 packages with the tax return, coordinates with certifying acceptance agents when you cannot leave your passport, and helps employers and newcomers fix SSN and ITIN mismatches. We do not give immigration advice. See our individual returns for newcomers and NRIs and relocation and immigration tax planning pages.

Frequently asked questions

General information only. It is not tax, legal, accounting or immigration advice for your situation, and rules change; confirm the current rules with the official source or a licensed professional in the relevant country.