Because you are filing your tax return as an attachment to your ITIN application, you should not mail your return to the address listed in the Form 1040, 1040A or 1040EZ instructions. Instead, send your return, Form W-7 and proof of identity documents to:

Internal Revenue Service
Austin Service Center
ITIN Operation
P.O. Box 149342
Austin, TX 78714-9342

You may also apply using the services of an IRS-authorized Acceptance Agent or visit an IRS Taxpayer Assistance Center in lieu of mailing your information to the IRS in Austin. TACs in the United States provide in-person help with ITIN applications on a walk-in or appointment basis. Applicants outside the United States should contact an overseas IRS office to find out if that office accepts Form W-7 applications. The IRS's ITIN Unit in Austin issues all numbers by mail.

When should I apply for an ITIN?
You should complete Form W-7 as soon as you are ready to file your federal income tax return, since you need to attach the return to your application.

If you meet one of the exceptions and do not need to file a return, submit Form W-7, along with the documents required to meet your purpose for needing an ITIN, as soon as possible after you determine that you are covered by that exception.

You can apply for an ITIN any time during the year; however, if the tax return you attach to Form W-7 is filed after the return's due date, you may owe interest and/or penalties. You should file your current year return by the April 15 deadline to avoid this.

How and when can I expect to receive my ITIN?
If you qualify for an ITIN and your application is complete, you will receive a letter from the IRS assigning your tax identification number, usually within four to six weeks. The IRS has changed from an ITIN card to an authorization letter to avoid any possible similarities with a Social Security Number card. Current ITIN holders' cards will not be replaced; they should continue to use the numbers previously issued when they need to supply identifying numbers for tax purposes.

If you have not received your ITIN or other correspondence six weeks after applying, you may call the IRS to find out the status of your application.

Where can I get help with my ITIN application?
You may call the IRS toll-free at 1-800-829-1040 for information and help in completing your Form W-7 and your tax return, or to check on the status of your application six weeks after submitting Form W-7.

Assistance is also available by appointment at IRS Taxpayer Assistance Centers (TACs) in the United States to provide in-person help with ITIN applications on a walk-in or appointment basis. Applicants outside the United States may contact an overseas IRS office to find out if that office accepts Form W-7 applications.

You may also use the services of an IRS-authorized Acceptance Agent.

What is an Acceptance Agent?
An Acceptance Agent is an individual, business or organization (college, financial institution, accounting firm, etc.) authorized by IRS to assist individuals in obtaining ITINs. Certifying Acceptance Agents review applicants' documentation, complete a certificate of accuracy, and forward the certificate and application to the IRS for processing. Some Acceptance Agents may charge a fee.