Blue Cross Blue Shield Under Fire After Major Montana Data Leak

Massive Data Breach Exposes Personal Information Of Montanans

Potentially half of all Montana residents are at risk after a data breach exposed their names, addresses, billing, and medical data.

That's according to Blue Cross Blue Shield of Montana, which is now under investigation from a third party named Lynch Carpenter.

Montana Officials Call Breach “Deeply Disturbing”

The data breach wasn't just a short one-time thing; this was months of information being leaked and possibly stolen, as the data breach took place between November 8, 2024, and March 5, 2025.

Montana State Auditor and Commissioner of Securities and Insurance James Brown was quoted as saying this breach was “not just a technical lapse” but framed it as a “deeply disturbing incident with far-reaching and jaw-dropping consequences for our citizens.”

Worse still, Blue Cross Blue Shield had promised to contact affected customers and offer credit monitoring; however, Commissioner Brown said he was unaware that this was happening.

What Montana Residents Should Do Now?

All told there are 462,000 Montana residents who are members of Blue Cross Blue Shield of Montana (BCBSMT), and Commissioner Brown said he's looking out for them, stating on X, formerly known as Twitter.

Montana is my home—and protecting our people is my job. We’ve launched a full-scale investigation into the Blue Cross Blue Shield data breach held by a 3rd party contractor to get answers and if the law was not followed to deliver accountability.

If you feel you've had your information compromised, make sure to look over your "Explanation of Benefits" statements and report suspicious activity immediately. You can also visit the Montana Commissioner of Securities and Insurance website here.

Sources: Lynch Carpenter, NBC Montana, KTVH, Newsweek