San Bernardino County Reports Arrowhead Medical Center Data Incident

San Bernardino County, acting for Arrowhead Regional Medical Center, filed a data breach notification in California on September 28, 2026. The incident, currently under investigation, potentially exposed sensitive patient information from the medical center's systems.

State: California
Breach date: August 28, 2026
Reported: September 28, 2026

What may have been exposed

Full Name
Date of Birth
Social Security Number
Medical Record Number
Health Insurance ID Number
Diagnosis and Treatment Information
Prescription Information
Provider and Treatment Dates

San Bernardino County, which operates Arrowhead Regional Medical Center (ARMC) in California, reported a data security incident to regulatory authorities. The filing, dated September 28, 2026, indicates an unspecified type of breach that occurred on August 28, 2026.

Public filings state that the exposed information includes Full Name, Date of Birth, Social Security Number, Medical Record Number, Health Insurance ID Number, Diagnosis and Treatment Information, Prescription Information, and Provider and Treatment Dates. The number of individuals affected by this incident remains unspecified in the available reports.

Exposure of such comprehensive personal and health-related data carries significant risks. Individuals whose information was compromised may face an increased risk of identity theft, medical identity theft, and various forms of fraud. Unlike financial data, core identity and medical records are difficult to change once exposed.

While an investigation into the incident is ongoing, individuals who receive notification letters should remain vigilant. It is generally recommended to regularly monitor financial statements, explanation of benefits (EOB) forms, and credit reports for any suspicious activity. Consider placing a fraud alert or security freeze on your credit files.

Furthermore, review any healthcare statements or communications from Arrowhead Regional Medical Center or your health insurer for unusual charges or services. If you suspect any fraudulent use of your medical information, contact your healthcare provider and insurance company immediately. This information is based on public disclosures made to state regulators.

What to do if you were affected

Based on the categories of information reported in this filing, these steps can help limit the risk of identity theft and fraud.

Freeze your credit
Place a free credit freeze with Equifax, Experian, and TransUnion. A freeze blocks new accounts from being opened in your name and can be lifted anytime.
Check for medical identity theft
Review the Explanation of Benefits statements from your health insurer for services or claims you never received, which can signal misuse of your medical identity.
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.

Source: California Attorney General filing

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