Contact Us

To help us better serve you, let's start with the reason you're contacting us.

Please do not include personal information (like your account number or social security number). For account specific questions or application status please login to Alliant Online Banking to send us a message or call us at 800-328-1935.

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Need help immediately?

We're always available by phone




Lost or Stolen Card

Credit Card: 866-444-8529
ATM/Debit Card: 800-328-1935

International Calls



TTY/TTD: 800-328-1935

Bank Routing Number


P.O. Box for Credit Card Payments

Alliant Credit Union P.O. Box 1666 Des Plaines, IL, 60017-1666

P.O. Box for Mortgage Loan Payments

Alliant Credit Union P.O. Box 1098 Des Plaines, IL, 60017-1098

P.O. Box for Deposits and Loan Payments

Alliant Credit Union P.O. Box 2387 Des Plaines, IL, 60017-2387

Do not use old deposit tickets, loan coupons or mailing labels that indicate an address other than the address listed above. Save time & money - deposit your checks via our mobile app.

We only accept cash deposits via select ATMs. Please use our ATM locator on our mobile app or via Online Banking.