How to apply for an Individual Taxpayer ID Number (ITIN) when filing tax

If you do not yet have an ITIN, you can include the application in your tax filing. Follow these steps to apply for an ITIN and file your tax return:

1. Complete IRS Form W-7.
2. Complete your federal and state tax returns using the number 999-88-9999 in place of a Social Security Number.
3. Print the tax returns and cross off the 999-88-9999 from the SSN field. Do not attempt to e-file your return.
4. Write "Applying for ITIN; Application attached" next to the SSN field.
5. Mail the signed federal return, the completed Form W-7, and all documentation required by the Form W-7 Instructions to the address specified in the Form W-7 Instructions. (Alternatively, you may choose to take all this information in-person to a local IRS office for processing.)
6. If you need to file a state tax return: Mail the signed state return and a copy of Form W-7 to your state's regular filing address.

Source: Turbotax
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