BAC limits in South Dakota
The legal blood-alcohol limit in South Dakota is 0.08% for drivers age 21 and older, 0.02% for drivers under 21, and 0.04% for anyone operating a commercial vehicle, regardless of age. A driver can be convicted of DUI in South Dakota below those numbers if a test or officer observation shows actual impairment — the BAC threshold is a per-se floor, not a safe harbor.
Implied consent
By accepting a South Dakota driver license or learner's permit you give implied consent to a breath, blood, or urine test if you are lawfully arrested for DUI. Refusing the chemical test triggers an automatic license suspension separate from — and in addition to — any criminal DUI penalty. The arresting officer is required to inform you of the consequences before you decide.
For a deeper read on this topic across all 50 states, see our right-of-way, speed limits, and alcohol and drugs articles.
Penalties for a first offense
A first DUI in South Dakota typically brings license suspension, fines that can exceed $1,000 with court costs, mandatory alcohol education, possible jail time, and an ignition interlock device requirement on any vehicle you drive after reinstatement. To get the license back you usually need to pay the $50 reinstatement fee and file an SR-22 certificate of insurance for several years.
Zero tolerance for under-21 drivers
If you are under 21 in South Dakota, the BAC threshold drops to 0.02%. That number is low enough that even a single drink can trigger it. A zero-tolerance suspension does not require a DUI arrest — a roadside breath test alone can produce an immediate administrative suspension that runs concurrently with any criminal case.
Open containers, marijuana, and prescription drugs
Open containers of alcohol in the passenger area of a vehicle are illegal in passenger area in South Dakota. Marijuana DUI in South Dakota is enforced under the same impaired-driving statute as alcohol, and there is no per-se THC limit you can rely on — any amount that impairs is illegal. Prescription drugs are not a defense; if a medication impairs your driving, you can be charged exactly as you would for alcohol.
Quick facts about South Dakota
- Capital: Pierre
- Minimum permit age: 14
- Current permit fee: $28
- Supervised hold period: 6 months
- Adult BAC limit: 0.08% · Under-21 BAC: 0.02%
- Default speed limits: 80 mph rural Interstate, 65 mph urban Interstate, 25 mph residential, 15 mph school zone
- Handheld phone use: banned
- Vision standard: 20/40 acuity in at least one eye, corrected or uncorrected
- Reinstatement fee after suspension: $50
- Official source: SD DPS
Other South Dakota guides on PermitPrep
Each link below opens a dedicated South Dakota page. Every guide is built from the same official SD DPS handbook so the rules stay consistent across topics.
- South Dakota Permit Practice Test — Practice test for South Dakota drivers.
- South Dakota Driving Permit Guide — Permit guide for South Dakota drivers.
- South Dakota Road Signs Test — Signs test for South Dakota drivers.
- South Dakota Traffic Laws Summary — Traffic laws for South Dakota drivers.
- South Dakota Right-of-Way Rules — Right of way for South Dakota drivers.
- South Dakota Speed Limits Explained — Speed limits for South Dakota drivers.
- South Dakota Cell Phone Laws — Cell phone laws for South Dakota drivers.
- South Dakota Parking Rules — Parking for South Dakota drivers.
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