Mainstreet Credit Union Reports Data Incident to Indiana AG

Mainstreet Credit Union has formally reported a data security incident to the Indiana Attorney General's office. This filing indicates that unauthorized access to the financial institution's systems occurred on January 12, 2026, with the official report submitted on May 4, 2026.

While the specific types of personal information involved are not detailed in the public record, Mainstreet Credit Union's notification letters confirm that the information held within their systems may have been compromised. The credit union is a financial entity that maintains sensitive data necessary for managing accounts and regulatory compliance.

According to the public filing, an investigation into the incident is currently underway. Customers who received a data breach notification from Mainstreet Credit Union are advised that their personal data may be at risk due to this unauthorized access.

As a general precaution, it is recommended to remain vigilant for any unusual activity across your financial accounts. Regularly review account statements and credit reports for discrepancies or unfamiliar transactions. You are entitled to a free copy of your credit report annually from each of the three major credit bureaus.

Additionally, be wary of unexpected communications, such as emails, text messages, or phone calls, that request personal information. These could be phishing attempts. Consider changing passwords for any online accounts where you may have reused credentials that were also used with Mainstreet Credit Union.