Does My Foreign Spouse Need an ITIN?

An Individual Taxpayer Identification Number, or ITIN, is a tax processing number issued by the Internal Revenue Service (IRS). It provides a unique identifier for individuals who have a federal tax filing requirement but are not eligible for a Social Security Number (SSN). An ITIN is strictly for tax administration and does not authorize work in the U.S. or provide eligibility for Social Security benefits.

Determining the Need for an ITIN

The most common reason a foreign spouse needs an ITIN is for the couple to file a joint tax return. To use the Married Filing Jointly (MFJ) status, the U.S. person must elect to treat their nonresident alien spouse as a U.S. resident for tax purposes for the entire year. When this choice is made, the foreign spouse’s worldwide income becomes subject to U.S. taxation, and an ITIN is mandatory to list them on the tax return.

This election allows the couple to access the MFJ tax brackets and standard deduction, which are often more favorable than those for other filing statuses. The IRS cannot process a joint return that includes a foreign spouse without an ITIN. This election is a binding choice for that tax year and remains in effect for future years unless revoked or terminated.

If the U.S. spouse chooses the Married Filing Separately (MFS) filing status, an ITIN is generally not required for the foreign spouse. On an MFS return, the U.S. spouse enters “NRA” (for Nonresident Alien) in the space for the spouse’s Social Security Number. Since the foreign spouse’s income is not reported on this return, an IRS-issued identification number is not needed.

A U.S. person married to a nonresident alien may qualify to file as Head of Household (HOH) in certain situations. This is possible if the taxpayer is considered unmarried for tax purposes because their spouse was a nonresident alien at any point during the year and the couple does not file a joint return. To qualify for HOH status, the taxpayer must have paid more than half the cost of keeping up a home for a qualifying person. The nonresident alien spouse cannot be the qualifying person; the taxpayer must have another qualifying individual, such as a child or relative.

Required Documentation for the ITIN Application

A completed U.S. federal income tax return must be attached to the ITIN application, Form W-7. The application cannot be submitted on its own and must be filed alongside the tax return that creates the need for the number. The tax return should be fully prepared but left unsigned, as it will be processed once the ITIN is assigned.

The application is Form W-7, Application for IRS Individual Taxpayer Identification Number. This form requires the applicant’s full legal name, foreign residential address, date and country of birth, and country of citizenship. The applicant must also check a box indicating the reason for applying, which for a foreign spouse on a joint return is typically “Spouse of U.S. citizen/resident alien.”

Proof of foreign status and identity is required. A valid, unexpired foreign passport is the only document that can be submitted by itself to prove both identity and foreign status. If a passport is not available, the applicant must provide a combination of at least two other documents from the IRS-approved list, such as a national identity card or a civil birth certificate. All documents must be either originals or certified copies from the issuing agency, as notarized copies are not accepted.

The ITIN Application Process

There are three methods for submitting the application package, which consists of Form W-7, the tax return, and identity documents. The most common method is mailing it to the IRS processing center in Austin, Texas, using the address in the Form W-7 instructions. Using a trackable mail service is recommended for monitoring the delivery of original documents.

A second option is to use an IRS-authorized Acceptance Agent. An agent can verify the applicant’s original identity documents and forward certified copies with the application to the IRS. This allows the applicant to avoid mailing original documents.

The third method is to schedule an appointment at a designated IRS Taxpayer Assistance Center (TAC). An IRS employee will review and verify the original identity documents in person, return them immediately, and forward the application for processing. This method is secure but requires scheduling an appointment in advance.

After submission, the IRS will review the application. Processing time ranges from 7 to 11 weeks but can be longer during peak tax season or for applications from abroad. Once approved, the IRS will mail a letter with the new ITIN, process the attached tax return, and return the original identity documents.