Missouri DWI Laws Explained

By Javier Marín, Editor·Last reviewed September 2026·How we check this

Missouri charges impaired driving under RSMo § 577.010 as Driving While Intoxicated (DWI) — Missouri does not use the term DUI. A DWI arrest triggers two parallel processes: a criminal case in county court and an administrative suspension by the Missouri Department of Revenue. Missouri also operates a unique 30-day suspension followed by a 60-day Restricted Driving Privilege (RDP) for first-offense BAC failures.

The legal threshold

Missouri's per-se DWI thresholds:

Adults 21+: 0.08% BAC.
BAC 0.15% or higher: aggravated DWI with enhanced penalties.
Drivers under 21: 0.02% BAC (zero-tolerance Abuse and Lose suspension).
Commercial drivers (CDL): 0.04% BAC.
Boating, snowmobile, off-road: 0.08% BAC under separate statutes.

Missouri also charges DWI on impairment evidence below 0.08% under § 577.010 — the prosecution must prove the driver was operating the vehicle while in an "intoxicated condition" by alcohol, drugs, or controlled substances.

The 30-day administrative suspension

After a Missouri DWI arrest where the BAC was 0.08% or higher, the arresting officer typically takes the driver's license on the spot and issues a 15-day temporary driving permit. The administrative suspension timeline:

30-day "hard" suspension: no driving for the first 30 days after the suspension takes effect.
60-day Restricted Driving Privilege (RDP): after the hard suspension, a 60-day RDP allows limited driving for work, school, medical care, treatment, and child custody — but only with an ignition interlock device installed.
Full reinstatement: at the end of the 90-day combined period, full driving privileges resume after payment of the reinstatement fee and proof of SR-22 insurance.

The driver has 15 days from arrest to request an administrative hearing with the DOR to challenge the suspension. The hearing is separate from any criminal case and addresses three narrow questions: was there probable cause for the stop, was the driver arrested for an alcohol-related offense, and was the BAC at or above 0.08%.

First-offense criminal penalties

A first DWI in Missouri is a Class B misdemeanor, carrying:

Up to 6 months in county jail.
A fine of $500 to $1,000, plus court costs.
Court-ordered license revocation that runs concurrent with the administrative suspension, typically 30 days followed by RDP.
Mandatory completion of a Substance Abuse Traffic Offender Program (SATOP) before reinstatement.
2 years of probation in many counties.
Mandatory ignition interlock device (IID) for the duration of any RDP and for at least 6 months of unrestricted driving thereafter.
SR-22 insurance filing for 3 years from reinstatement — see Missouri car insurance.

Ignition Interlock Devices

Missouri requires an IID for every DWI offender granted a Restricted Driving Privilege or Limited Driving Privilege. The IID is paid by the driver (typically $70 to $130 per month plus a $100 install fee) and prevents the vehicle from starting if breath alcohol is detected. Failed tests are reported to the DOR, and a pattern of failures revokes the privilege and imposes the full original suspension. IID duration is 6 months minimum for first offenses and rises with subsequent offenses.

Aggravating factors

Missouri penalties escalate when:

BAC at or above 0.15% — aggravated DWI with enhanced fines and IID requirement.
A passenger under 17 in the vehicle (separate Class D felony charge for endangering the welfare of a child).
An accident with serious injury or death (DWI Resulting in Injury or DWI Resulting in Death — Class B and Class A felonies).
Driving while license already suspended for DWI (Class E felony).
A prior DWI within Missouri's lookback window for enhancement.
Refusing the chemical test (1-year administrative suspension and the criminal case can still proceed).

Repeat offenses

Missouri's Persistent Offender designation triggers when a driver has two prior DWI convictions in any timeframe — and produces a Class E felony charge (up to 4 years prison and $10,000 fine) on the third offense. A Chronic Offender designation applies after four total DWI convictions in any timeframe, producing a Class C felony with up to 10 years prison. Missouri's lookback for enhancement is essentially lifetime — DWI convictions never roll off for purposes of the persistent and chronic designations, even if they roll off for points.

Drivers under 21 face Missouri's Abuse and Lose law: any conviction involving alcohol or drugs (DWI, minor in possession, fake ID for alcohol purchase) triggers a 90-day to 1-year license suspension separate from any criminal sentence. See the teen license page for the consequences during the intermediate stage.