South Dakota Oversize & Overweight Permits
Legal to 8'6" wide, 14' high, 80,000 lb. Over that you need a permit. Single-trip runs $25; superloads climb toward $2,000. Escorts stay light on the open road: one over 16' wide on the Interstate, over 20' on state highways. The Black Hills tighten that to a front escort past 10'. Police ride superloads over 12' wide, 16' high, or 200,000 lb. Wide, tall, or long loads are daylight-only. Confirm hours on the permit.
When South Dakota needs a permit
Legal to 8'6" wide, 14' high, 80,000 lb. Over that you need a permit. Single-trip runs $25; superloads climb toward $2,000. Escorts stay light on the open road: one over 16' wide on the Interstate, over 20' on state highways. The Black Hills tighten that to a front escort past 10'. Police ride superloads over 12' wide, 16' high, or 200,000 lb. Wide, tall, or long loads are daylight-only. Confirm hours on the permit.
Thresholds, escorts, and curfews
- Legal max before a permit: Permit needed over 8'6" wide, over 14' high, over 80,000 lb, or over SD's legal length (45' single unit; long combinations are allowed).
- Escort / pilot car: One escort over 16' wide on the Interstate, over 20' wide on state highways. A front escort is required over 10' wide in the Black Hills area on state highways. Multiple escorts if the load reaches more than 2' into an adjacent lane. Police escort superloads over 12' wide, 16' high, or 200,000 lb.
- Superload: Manual engineering review kicks in at gross over 200,000 lb, a load both overweight and over 12' wide, or over 16' high. Superloads carry police escorts and can run toward $2,000. Expect route and bridge review; SD publishes no fixed lead time.
- Travel curfew: SD is comparatively open, but wide, tall, or long loads are daylight-only, with night limits above 14'6" high, 45' single, or 110' combination on the Interstate. Overweight loads cap at 65 mph. Confirm weekend and holiday no-move windows on the permit.
- Permit fee: Single-trip $25. Extended-period permits $60. Longer-combination-vehicle permit $100 per book of ten. Superloads run up to about $2,000.
South Dakota Oversize Permit FAQ
When do I need an oversize permit in South Dakota?
Does South Dakota require a pilot car or escort?
Can I move an oversize load at night or on weekends in South Dakota?
What does an oversize permit cost in South Dakota?
Reference information for planning, not legal advice. Traffic laws change and this can be out of date, so always confirm the current statute and obey posted signs before you rely on it. Last reviewed July 2026. Source: https://sdtruckinfo.sd.gov/rules-regulations/motor-carrier-handbook/chapter-6/permits/. See our Terms & Disclaimer.
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