Guardian Credit Union Breach Exposes Social Security Numbers

Guardian Credit Union, a member-owned, not-for-profit credit union headquartered in Oak Creek, Wisconsin, disclosed a data breach that may have exposed sensitive personal and financial information.

The credit union became aware of suspicious activity and launched an investigation with the support of third-party forensic specialists to confirm the security of its network. After completing that investigation, Guardian Credit Union engaged a separate third party to conduct a review of the information at risk.

The types of personal information exposed in the breach included Social Security numbers, driver's license information and financial account information such as credit or debit card numbers.

The breach was disclosed to the Massachusetts Office of Consumer Affairs and Business Regulation and to the Vermont Attorney General on Aug. 6, 2026.

Guardian Credit Union's response

Guardian Credit Union is offering affected individuals 24 months of complimentary credit monitoring and identity protection services through Experian IdentityWorks. Individuals who received a notification letter can enroll by visiting the Experian IdentityWorks enrollment page and entering the activation code included in their letter.

Enrollment must be completed by the deadline printed in each person's letter.

Affected individuals who have questions can call Guardian Credit Union's dedicated assistance line at 888-616-9569, available Monday through Friday from 9 a.m. to 9 p.m. Eastern Time, excluding U.S. holidays.

Individuals can also reach the credit union by email at privacyevent@guardiancu.org. For questions about the Experian IdentityWorks product or identity restoration services, individuals can contact Experian at 1-877-288-8057 by Dec. 31, 2026.