South Dakota DUI Laws Explained

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

A South Dakota DUI charge under SDCL § 32-23-1 triggers two parallel processes: a criminal case in circuit or magistrate court, and an administrative license action by SD DPS. Both move quickly. The administrative window is short, the IID program is mandatory for many offenders, and the aggravated tier at 0.17% BAC adds penalties that surprise first-time offenders.

The legal threshold

South Dakota's per-se DUI thresholds:

Adults 21+: 0.08% BAC.
Drivers under 21: 0.02% BAC under the state's zero-tolerance law.
Commercial drivers (CDL): 0.04% BAC.
Aggravated DUI: 0.17% BAC or higher - separate elevated penalties.

South Dakota also charges DUI on impairment evidence below 0.08% under SDCL § 32-23-1(2) - the "under the influence" subsection that does not require a specific BAC. Drug-impaired DUIs (controlled substances, prescription medications, marijuana) fall under the same statute.

The implied consent process

By driving on a South Dakota road, every driver gives implied consent to chemical testing if lawfully arrested for DUI. Refusing the test results in:

A 1-year minimum license revocation on the first refusal.
A 2-year minimum license revocation on the second refusal within 10 years.
The refusal is admissible at trial.
The driver may still be convicted of DUI on impairment evidence even without a measured BAC.

Administrative license revocation

After a DUI arrest where the BAC was 0.08% or higher (or the driver refused testing), the arresting officer may take the South Dakota driver license on the spot and issue a notice of revocation. The administrative revocation is separate from the criminal case:

30-day to 1-year revocation on a first-offense BAC failure.
1-year revocation on a first-offense refusal.
Longer revocations on subsequent offenses.

Drivers can request an administrative hearing within 30 days of the notice. See suspended license for reinstatement steps.

First-offense penalties

A first-offense DUI conviction in South Dakota is a Class 1 misdemeanor, carrying:

Up to 1 year in county jail (often suspended on first offenses without aggravating factors).
A fine of up to $2,000, plus court costs.
License revocation of 30 days to 1 year, with potential for early reinstatement under the IID program.
Mandatory chemical dependency evaluation and any recommended treatment.
Mandatory participation in the 24/7 Sobriety Program in many counties for repeat or aggravated cases.
Probation up to 1 year.
SR-22 financial responsibility filing for at least 3 years - see South Dakota car insurance.

The 24/7 Sobriety Program

South Dakota pioneered the 24/7 Sobriety Program, a court-ordered abstinence-based supervision option for repeat or high-BAC DUI offenders. Participants test twice daily for alcohol use, typically using a portable breath device, transdermal monitor, or drug patch. Failed tests trigger immediate sanctions - often a brief jail stint - rather than waiting for a full probation hearing. The program has been credited with significant reductions in DUI repeat offenses and is unique to South Dakota's approach.

Ignition Interlock Devices (IID)

South Dakota's IID program is available as an early reinstatement option for first-offense DUIs and is generally required for second and subsequent offenses, BAC at or above 0.17%, and refusal cases. The device is installed at the driver's expense - typically $70-$120 per month plus a $100-$150 install fee - and prevents the vehicle from starting if a measurable BAC is detected. Tampering or repeated failed tests can extend the IID period.

Aggravating factors

South Dakota DUI penalties escalate when any of these apply:

BAC at or above 0.17% (aggravated DUI tier).
An accident with injury or property damage.
A child under 14 in the vehicle (separate child endangerment charge possible).
Excessive speed at the time of arrest.
A prior DUI within the 10-year lookback window.
Refusing chemical testing.

Repeat offenses

A second DUI conviction within 10 years is a Class 1 misdemeanor with mandatory minimum jail time, longer license revocation, longer IID requirement, and 24/7 Sobriety Program enrollment. A third DUI within 10 years is a Class 6 felony with potential prison time, $4,000 fine, and 1-year minimum revocation. A fourth or subsequent DUI is a Class 5 felony.