What identification do I need to apply for Alliant membership? In addition to completing an Alliant membership application, you’ll need to provide the identification information and documents listed below: Category 1: Provide one of the following: A Social Security Number (SSN) An unexpired ITIN and a completed W-8BEN form Category 2: Provide a copy of one form of valid ID from this list: U.S. driver’s license State ID Signed U.S. passport Permanent resident card Foreign passport Category 3: Provide a copy of one form of address verification from this list (not required for minors 17 and under): Utility bill Lease agreement Mortgage statement Vehicle registration card Voter registration card Also, if you’re applying for first-time membership and your relative or domestic partner is a member, you’ll need their first and last name and their qualifying employer, organization or community. You can opt to also provide your family member’s membership account number, but it isn’t required. If you can't apply for Alliant membership online, you can complete a hard copy application and return it to Alliant one of three ways: Mail your completed hard copy application to Alliant Credit Union / 11545 W. Touhy Ave. / Chicago, IL 60666. Fax your completed hard copy application to 773-462-2124. Call us at 800-328-1935 to request that we send you a secure email with instructions that will enable you to securely upload your completed hard copy application.