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Montana DUI / DWI Limits (2026)

Info: In Montana the adult DUI limit is 0.08% blood alcohol, with an aggravated offense at 0.16%, and drivers under 21 are held to a zero-tolerance limit of 0.02%.

InfoVerified May 31, 2026

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Official source: dojmt.gov →

General legal information, not legal advice — verify important decisions with a licensed attorney.

DUI / DWI Limits in states bordering Montana

The same rule in each neighboring state LawLert has verified, from that state’s own official source.

IdahoInfo
In Idaho the DUI limit for drivers 21 and older is 0.08% blood alcohol (I.C. 18-8004), and the limit for drivers under 21 is 0.02%.
Verified May 31, 2026 · Source: legislature.idaho.gov · Full Idaho rule →
North DakotaInfo
In North Dakota a DUI is 0.08% blood alcohol or higher for adults 21 and older (per se), the limit for drivers under 21 is 0.02%, and commercial drivers are limited to 0.04.
Verified May 31, 2026 · Source: ndlegis.gov · Full North Dakota rule →
South DakotaInfo
In South Dakota the per se limit for adults is 0.08% blood alcohol, and drivers under 21 are held to a zero-tolerance limit of 0.02%.
Verified May 31, 2026 · Source: sdlegislature.gov · Full South Dakota rule →
WyomingInfo
In Wyoming the per se limit for adults is 0.08% blood alcohol, and drivers under 21 are held to a zero-tolerance limit of 0.02%.
Verified May 31, 2026 · Source: wyoleg.gov · Full Wyoming rule →

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