An Individual Taxpayer Identification Number (ITIN) is a tax processing number issued by the Internal Revenue Service (IRS) to individuals who are required to have a U.S. taxpayer identification number but who do not already have and are not eligible to obtain a Social Security Number (SSN) from the Social Security Administration (SSA).

Stipend recipients and those who have taxable scholarships, but are not employed, are required to obtain an ITIN. If, however, you have an offer of employment, you must apply for an SSN instead of an ITIN.

What is an Individual Taxpayer Identification Number?

The ITIN is a tax processing number issued by the Internal Revenue Service (IRS).  It is a nine digit number that always begins with the number 9 and has a 7 or 8 as the fourth digit; example, 9xx-7x-xxxx.

Note: the 999/998 number assigned to you by Washington University upon your admission is not an ITIN.

The IRS issues ITINs to foreign nationals who are required to have a U.S. taxpayer identification number, but who are not eligible for a Social Security Number (SSN).  It is important to note the ITIN is not valid outside of the tax system.    You are able to complete rental applications and set-up utilities without an SSN.

Who needs an ITIN?

The IRS issues ITINs to foreign nationals and others who have federal tax reporting or filing requirements and do not qualify for SSNs. A non-resident alien not eligible for an SSN who is required to file a U.S. tax return only to claim a refund of tax under the provisions of a U.S. tax treaty needs an ITIN.

Examples of individuals who may need an ITIN include:

  • Taxable scholarship recipients who are not also employed;
  • Stipend recipients who do not have separate employment income;
  • Nonresident aliens required to file a U.S. tax return;
  • U.S. resident aliens for tax purposes (based on days present in the United States) filing a U.S. tax return;
  • Dependents or spouses of a U.S. citizen/resident alien;
  • Dependents or spouses of a nonresident alien visa holder

What if I have been in the U.S. and already have an SSN?

You do not need to have both an SSN and ITIN. If you already have an SSN from a previous U.S. job, you do not need to apply for an ITIN. SSNs are assigned for life, so you should use the SSN you already have, and make sure it has been reported to Payroll Services.

I don’t have any number yet – How do I apply for an ITIN?

In order to apply for the ITIN, you must the file Form W-7, Application for IRS Individual Taxpayer Identification Number (PDF) with certification of your immigration documents to the IRS.

Documents Needed

  1. Completed Form W-7: Application for IRS Individual Taxpayer Identification Number (PDF)
  2. Passport
  3. Current entry visa
  4. Most recent I-94
  5. Current I-20
  6. Financial aid, stipend or scholarship letter

When and Where to Apply

You can apply for an ITIN any time during the year; however, it is recommended you file as soon as possible as this can affect tax treaty benefits. The OISS has appointments available in September to assist you in the application/certification process.

After the appointment period has ended, you will have to go downtown to the local Taxpayer Assistance Center (TAC) located in the IRS office in downtown St. Louis.

1222 Spruce St.
St. Louis, MO 63103
8:30 a.m.-4:30 p.m.
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Office Information

Directions via MetroLink: Take the blue line to the Civic Center station. Exit and walk 1 block down Spruce Street. The IRS building is at the corner of Spruce St. and S. Tucker Blvd.

What happens after my application is submitted?

You will receive a letter from the IRS assigning your tax identification number usually within seven weeks. (Sometimes they are processed in 3-4 weeks, but it could take as long as 7 weeks). Once you get your number, you must report it in FNIS and also to Payroll Services, so it can be added to the HR and payroll systems.

What if I get a job later or otherwise become eligible for an SSN?

If at any time you become eligible for an SSN, you need to apply for the SSN and report the new number to Payroll Services.

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