How to Get an ITIN Number

By eHow Contributor

An Individual Taxpayer Identification Number, often shortened to simply ITIN, is a type of tax identification number in the U.S. for individuals who need to file and pay federal taxes. While most U.S. residents have a Social Security number, which acts as a tax ID number for taxpaying purposes, resident and non-resident aliens are not eligible for an SSN. Instead, non-citizens can get an ITIN number to file and pay income taxes.

Determine if you need to get an ITIN number. Individuals who do not have a Social Security number and are not eligible to receive one, but who are required to file, pay or otherwise provide information through a federal tax return must get an ITIN number. This includes resident aliens, non-resident aliens, spouses of resident aliens, dependents of resident aliens, spouses of non-resident aliens who hold a visa and dependants of non-resident aliens who hold a visa. Permanent residents and U.S. citizens who do not have a Social Security number, but who qualify to obtain one, are not eligible to get an ITIN. Instead, they must apply for a Social Security number and use this for federal tax-related purposes.

Obtain revised IRS Form W-7 (Application for IRS Individual Taxpayer Identification Number). You can obtain one by visiting your local IRS office in person, or contact the IRS helpline at (800) TAX-FORM. You can also download and print Form W-7 from the IRS website at home.

Complete Form W-7 by providing your personal information, including your name, address, date and location of your birth. If you are an applicable spouse or dependent, you will also need to provide the Social Security number or ITIN number of your spouse or guardian. Sign the bottom when finished, make a copy of the completed form and retain the copy for your personal records.

Organize the required supporting documents for your application to get an ITIN number. You are required to provide supporting documents to both demonstrate your identity and prove your foreign status in order to get an ITIN. Examples of supporting documents for identity include a valid passport, USCIS identification card or a U.S. photo driver's license; examples of supporting documents for foreign status include a valid passport, military identification card from your country of origin or a current national identification card.

Complete a federal tax return to submit along with your application to get an ITIN number. To have your application for an ITIN approved, you must submit a federal tax return unless you qualify as an exception to this requirement. Non-resident aliens who are required to get an ITIN to claim a tax treaty benefit are typically the only persons eligible for this exception, although you should review the IRS's exemption list to see if you qualify. If you do qualify and wish to take the exemption, you will need to provide documentation supporting the exception to get an ITIN number.

Submit your completed Form W-7, federal tax return or documents supporting your status as an exception, and your proof of identification and foreign status to the IRS by mail. If you submit original documents for proof of identification and/or foreign status, your documents will be returned to you after your application to get an ITIN number has been processed.