How to Find an ITIN Number

Updated on January 7, 2024

At a Glance

  • The Individual Taxpayer Identification Number (ITIN) is a unique identification number issued by the IRS for certain taxpayers who are required to file taxes but do not have a Social Security Number.
  • It is used solely for federal tax reporting purposes.
  • If you lose your ITIN, you must contact the IRS to retrieve it, and if it has expired, you need to apply for a new one.
  • Renewal can be done through mail, with an Acceptance Agent, or at an IRS Assistance Center, requiring supporting documents to prove identity and foreign status.

Tax season can be a very stressful time of the year. It combines the difficulty of navigating complex laws with the challenge of understanding your finances. One of the most important aspects of tax filing is your ITIN for immigrants. Read on if you have been asking yourself, ‘Where can I find my ITIN number?’

What is an ITIN Number?

The Individual Taxpayer Identification Number (ITIN) is how the Internal Revenue Service (IRS) keeps track of certain taxpayers in the United States. It is like the student numbers issued by colleges to identify their students.

Not every U.S. taxpayer has an ITIN. For U.S. citizens, the IRS identifies them using their Social Security Number (SSN), which is issued by the Social Security Administration. Read more here to understand the difference between an ITIN and an SSN.

However, some people are required to file a tax return in the U.S. but do not have a social security number. For these people, the IRS issues an ITIN.

ITINs are not issued automatically. You will not have an ITIN unless you applied for one in the past. Your ITIN serves no purpose other than federal tax reporting.

How to Look Up Your ITIN Number?

Unsure of your TIN? No need to worry. This number is mandatory on all tax-related documents by the IRS.

1099 or W2

Check any 1099 or W2 forms you have, as your TIN will be listed there. If these documents are unavailable, the IRS provides resources to assist in retrieving lost paperwork. Alternatively, you have other methods to determine your TIN for tax ID lookup purposes.

Checking Existing Tax Documents

Your TIN is a requirement on all tax documents, whether for personal or business purposes. For business owners, this number is also present on business licenses, permits, bank account documents, loans, and other relevant applications. Your business tax ID, or Employer Identification Number (EIN), will be listed on these. Additionally, your business credit report is another source to locate your TIN. For accountants, the Preparer Tax Identification Number (PTIN) is used in tax preparation services, making those documents another reference point.

Reaching Out to the IRS

For definitive information, contacting the IRS is your best option. Their business and specialty tax department is available Monday through Friday, from 7 am to 7 pm EST, at 800-829-4933. Be prepared to answer security authorization questions to access your TIN. Moreover, the government’s official website offers extensive resources and guidance for any further questions regarding tax ID lookup.

What Do You Do If You Lose Your ITIN Number?

Your ITIN is not like a social security number. It is issued by the IRS and is only used by the IRS. If you lose your ITIN, you will need to contact the IRS to get it back. The process of getting your ITIN from the IRS is simple if it has not expired: 

  1. Call the IRS toll-free helpline on 800-829-1040
  2. Answer the security questions to verify your identity
  3. Follow the instructions to receive your ITIN.

If the IRS is not able to tell you your ITIN, that might be because it has expired. That could happen if your ITIN has not been used to file a federal tax return in several years. 

If this is the case, you will need to apply for a new ITIN. The section below will explain the process of obtaining a new ITIN.

What to Do If Your ITIN has Expired

If your ITIN has expired, you must apply to renew it. There are three ways you can apply for a new or renewed ITIN with the IRS. Take a look below for how to renew an ITIN.

Apply for New ITIN by Mail

You can apply for a new ITIN by mail using the instructions listed below:

  1. Go to
  2. Download a Form W-7 and print it
  3. Fill in the W-7 with all of your details
  4. Gather supporting documents (Proof of identity/Foreign status document)
  5. Mail your completed W-7 and supporting documents to the ITIN Operation center.

The postal address for the ITIN Operation center is:

Internal Revenue Service

Austin Service Center

ITIN Operation

P.O. Box 149342

Austin, TX 78714-9342

The IRS requires you to mail in your original documents to complete this process. Certified copies will not be accepted. 

If you don’t want to take the risk of mailing important original documents, or if you will need them within 14 weeks of applying, it is better to use one of the in-person methods of applying for an ITIN.

Apply for New ITIN with Acceptance Agent

It is also possible to apply for a new ITIN in person at an IRS-authorised Certifying Acceptance agent. If you use this method, you still need to have and show your original supporting documents. The agent will make copies of them and certify them for your application. 

Visit the IRS website to find the list of Acceptance Agents for Form W-7 inside and outside the United States.

Apply for New ITIN at IRS Assistance Center

The third way to apply for a new ITIN is at an IRS Assistance Center. As with an Acceptance Agent, you will not need to mail anything in. You just need to provide your supporting documents and completed Form W-7 to the IRS representative at the Center.

When this process is complete, the IRS will issue your new ITIN through the mail.

You should apply for an ITIN if you are requested to file or report your tax return but you don’t have a social security number. If you are required to file federal income tax and you do not already have an ITIN, you will need to file a form W-7 along with your tax return.

Whichever method you choose to apply for your ITIN, you only need to do so once. If you use your ITIN to file your tax return regularly, it will not expire and you will never need to renew it.

The list of supporting documents you can use is detailed in the next section.

Documents Needed to Renew Your ITIN

You will need to provide supporting documents to the IRS when you apply to renew your ITIN. Specifically, you need to provide proof of your identity and your foreign status. 

The list below shows some of the documents you can use to support a Form W-7 Application for IRS Individual Taxpayer Identification Number:

  • Passport (the only stand-alone document): Foreign Status and Identity
  • U.S. Citizenship and Immigration Services (USCIS) photo identification: Foreign Status and Identity
  • Visa issued by the U.S. Department of State: Foreign Status and Identity
  • U.S. driver’s license: Identity Only
  • U.S. military identification card: Identity Only
  • Foreign driver’s license: Identity Only
  • Foreign military identification card: Foreign Status and Identity
  • National identification card (with name, photograph, address, date of birth, and expiration date): Foreign Status and Identity
  • U.S. state identification card: Identity Only
  • Foreign voter registration card: Foreign Status and Identity
  • Civil birth certificate: Foreign Status and Identity
  • Medical records (only for dependents under age 6): Foreign Status and Identity
  • School records (only for a dependent under age 18, if a student): Foreign Status and Identity.

At least one of the documents you provide must have a photograph of you, and none of the documents you provide are acceptable if they have expired. 

Birth certificates, medical records, and school records can only be used to prove foreign status if they were issued in a foreign country.

Why Won’t the IRS Send You Your Missing ITIN?

If you are wondering, ‘Where can I find my ITIN number?’ you might think the most obvious answer is, ‘At the IRS.’ Generally, that is the correct answer. You can call the IRS helpline at 800-829-1040 to retrieve your ITIN.

Unfortunately, this will not work for some people. Sometimes the IRS will not send your missing ITIN even if you do the procedure correctly. If that happens to you, it is probably because your ITIN has expired. If this is the case, you must renew your ITIN.

This may also happen if you do not have an ITIN. The IRS does not automatically issue ITINs, so you must have previously applied for one to have an ITIN.

Frequently Asked Questions (FAQ)

What is an ITIN Number?

An Individual Taxpayer Identification Number (ITIN) is a tax processing number issued by the Internal Revenue Service (IRS) in the United States. It’s used by individuals who are required to have a U.S. taxpayer identification number but do not have and are not eligible to obtain a Social Security Number (SSN).

Who needs an ITIN?

ITINs are needed by individuals who need to file U.S. taxes but are not eligible for an SSN, including non-resident aliens, some resident aliens, and dependents or spouses of U.S. citizens or resident aliens.

How can I find my ITIN Number?

If you’ve previously been issued an ITIN, it can be found on any tax return that you filed using it. The ITIN is a nine-digit number, similar in format to an SSN.

What if I lost or forgot my ITIN?

If you’ve lost or forgotten your ITIN, you can:

  1. Review previous tax returns for the number.
  2. Contact the IRS directly at 1-800-829-1040 (for individuals within the United States).
  3. Visit an IRS Taxpayer Assistance Center.

Can I look up my ITIN online?

No, for security reasons, you cannot look up your ITIN online. You’ll need to contact the IRS or check your previous tax documents.

How do I apply for an ITIN?

To apply for an ITIN, you need to fill out IRS Form W-7 and submit it along with your federal income tax return and proof of identity and foreign status documents.

How long does it take to get an ITIN?

The processing time for an ITIN application can vary but typically takes about 7 weeks. However, it may take longer during peak processing times or if additional documents are required.

Does an ITIN expire?

Yes, ITINs do expire. ITINs not used on a federal tax return for three consecutive years or those with middle digits 88, 90, 91, 92, 94, 95, 96, 97, 98, or 99 will expire.

Can I use an ITIN for identification purposes?

An ITIN is primarily for tax reporting purposes and should not be used as a personal identification number. It does not provide legal immigration status or work authorization.

What documents are required to apply for an ITIN?

To apply for an ITIN, you need to provide a completed IRS Form W-7, a federal income tax return, and original or certified copies of documents proving identity and foreign status.

Read More

Final Thoughts 

Your ITIN is a number that the IRS uses to identify you. If you are asking yourself, ‘Where can I find my ITIN number?’ there are some steps you can take. You can ask the IRS to tell you what your ITIN is by calling the helpline. If that doesn’t work, you need to apply for a new one. The application process can be done by mail or in person. It takes up to seven weeks for the IRS to issue a new ITIN or 14 weeks for applications by mail.

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Frank Gogol

I’m a firm believer that information is the key to financial freedom. On the Stilt Blog, I write about the complex topics — like finance, immigration, and technology — to help immigrants make the most of their lives in the U.S. Our content and brand have been featured in Forbes, TechCrunch, VentureBeat, and more.

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