ITIN (W-7) Application:           If you have certain US source income or otherwise US tax filing requirement and you are not eligible for an SSN, then you may need to apply for what's known as an Individual Taxpayer Identification Number (ITIN). Use Form W-7 to apply for ITIN.           Spouse ITIN- You may need ITIN for your spouse if you are eligible to file jointly.           Dependent ITIN : You may need to apply for ITIN of your dependents if you can claim them on your tax return.           You can apply for ITIN with your tax return. In case you need ITIN for business purpose you can apply anytime with your business documents.           You need to attach an original, or a certified or notarized copy, of an UNEXPIRED passport to your ITIN application form for both identity and foreign status proof.           IRS will accept certified or notarized copies of a combination (two or more) of the certain documents, in lieu of a passport, as below :           National identification card ,U.S. driver's license, Civil birth certificate Foreign driver's license, U.S. state identification card ,Foreign voter's registration card ,U.S. military identification card, Foreign military identification card etc.