State notification register
Montana data breach notification law: without unreasonable delay.
Montana's breach-notification obligations are set by Mont. Code Ann. 30-14-1704 et seq.. This page summarises the deadline to notify affected residents, the attorney general notification threshold, whether a private right of action exists, and the penalties for late or missing notification. Every provision is cited to its source statute and was verified in June 2026.
Individual deadline
No fixed day
Without unreasonable delay
AG notification
Required
All breaches affecting Montana residents
Private action
No
Only the Montana Attorney General may bring enforcement actions
Statute
MT
Mont. Code Ann. 30-14-1704 et seq.
Section MT.1
What the statute requires
Under Mont. Code Ann. 30-14-1704 et seq., a business that owns or licenses computerized personal information of Montana residents must notify affected individuals without unreasonable delay.
Attorney general or state-agency notification is all breaches affecting montana residents. Where required, the timeline is: when notice is provided to affected individuals.
Section MT.2
What triggers notification
Like most US state statutes, notification is triggered by the unauthorized acquisition of unencrypted, unredacted computerized personal information that compromises its security, confidentiality, or integrity. Two concepts recur across the states and apply here.
Encryption safe harbor
Personal information that was encrypted, and where the encryption key was not also acquired, generally does not trigger notification. A stolen device with full-disk encryption is typically a non-event; an unencrypted record, or an encrypted record where the key was exposed alongside it, is a reportable breach.
Who must be notified
- [1] Affected Montana residents: without unreasonable delay
- [2] Attorney general / state agency: all breaches affecting montana residents
- [3] Consumer reporting agencies where the breach is large-scale
Section MT.3
Penalties and enforcement
Unfair or deceptive trade practice; up to $10,000 per violation, plus restitution.
Private right of action: No. Only the Montana Attorney General may bring enforcement actions.
Primary source:Montana statute Mont. Code Ann. 30-14-1704 et seq.; verified June 2026 against state statutory summaries and the underlying statute text.
Section MT.4
How this compares to the strictest states
The strictest US deadlines are 30 days (California, Florida, Washington, Colorado, Maine, New York, New Jersey). The majority of states use a qualitative "without unreasonable delay" standard with no fixed day cap. Here is where Montana sits.
Montana does not set a numeric deadline. It uses a "without unreasonable delay" standard, which regulators interpret as days to weeks, not months. Organizations operating across multiple states should default to the strictest applicable clock, which can be as short as 30 days in states such as California, Colorado, Florida.
Cross-references
Index / All 50 states + DC
→The full register: deadline and AG threshold for every state.
Schedule 09 / Notification laws
→Global frameworks and the cost of notification.
01 / Breach cost calculator
→Estimate your Montana breach exposure, including notification cost.
Regulation / GDPR
→The 72-hour clock and 4%-of-revenue fine framework.
Cost / Notification
→Why notification is roughly 6% of total breach cost.
Schedule F / Reference Q&A
Frequently Asked Questions
Primary source:Montana data breach notification statute (Mont. Code Ann. 30-14-1704 et seq.). Provisions verified June 2026 against state statutory summaries (Recording Law US data-privacy series, 2026 edition), the IAPP US State Data Breach Notification Chart, Foley & Lardner's chart, and the underlying statute text.