How do I get an ITIN for my spouse or dependent who doesn't have an SSN?

You apply for an ITIN by filing Form W-7 along with the tax return on which the spouse or dependent appears, plus proof of identity and foreign status (usually a passport). You generally submit the W-7 and return together; the IRS issues the number and processes the return. To avoid mailing original documents, you can use an IRS-authorized Certifying Acceptance Agent or visit a designated IRS Taxpayer Assistance Center to verify documents in person. Processing typically takes several weeks, so file early in the season. People often request an ITIN for a nonresident spouse specifically so they can elect to file jointly and use the larger married-filing-jointly standard deduction. Note that ITINs can expire if unused for several years and must be renewed. Gather certified document copies before you start so the application isn't rejected for incomplete proof.