Data Breach Law Group Investigates the Mainstreet Credit Union Data Breach
By Data Breach Law Group | Posted on May 4, 2026 · Indiana
Miami, FL — Data Breach Law Group is investigating a data breach involving Mainstreet Credit Union, reported to the Indiana Attorney General on May 4, 2026. The firm is reviewing whether affected individuals have legal claims arising from the incident.
Mainstreet Credit Union is a financial institution that provides banking services, including personal savings, checking accounts, and loan products to its members. As a financial entity, the credit union maintains sensitive personal and financial records necessary for account management, credit reporting, and regulatory compliance. In 2026, the company officially reported a data security incident to the Indiana Attorney General, confirming that unauthorized access to their systems occurred. If you received a data breach notification letter from Mainstreet Credit Union, it indicates that your personal information held within their systems may have been compromised. This notice is intended to inform you of the incident and provide guidance on the steps you should take to protect your financial identity and monitor your accounts for suspicious activity.
If you were affected
Stay alert to targeted scams
Be cautious of calls, texts, or emails that reference this breach. Legitimate organizations won't ask you to confirm sensitive details through an unsolicited message.
Keep your notification letter
Save the notice you received. It documents that your information was involved and is often needed to enroll in any credit monitoring offered or to join a related legal claim.
Did you receive a letter from Mainstreet Credit Union?
A case review is free and confidential. Tell us about your letter and we will explain your options.