Transporting Livestock in South Dakota: Rules Every Hauler Needs to Know

South Dakota’s agriculture industry depends on the movement of cattle, hogs, sheep, and other animals across hundreds of miles of open highway every year. Whether you’re a rancher moving your own herd to a sale barn or a commercial carrier hauling livestock for hire, the state has a clear set of rules governing how that movement must happen — and the consequences for getting it wrong can range from a costly fine to an out-of-service order that leaves your animals stranded on the roadside.

This guide walks you through every major compliance area for livestock hauling in South Dakota: trailer registration, structural and safety standards, size and weight limits, animal welfare requirements, driver licensing, and what to expect at a roadside inspection. Use it as a practical checklist before your next haul.

Livestock Trailer Registration and Identification Requirements in South Dakota

Getting your trailer properly registered and identified is the first compliance step before any livestock haul. South Dakota processes all trailer titling and registrations through your local county treasurer’s office, so that is your starting point for any new trailer or ownership transfer.

Owners of trailers used with automobiles, pickups, and vans weighing less than 6,000 pounds must purchase a regular annual trailer plate, and there is no restriction on the weight carried by trailers licensed in this manner. If you are pulling a livestock trailer with a heavier commercial or declared-gross-weight truck, the registration pathway is different.

A trailer being pulled by a truck licensed under the declared gross weight schedule or a commercial licensed vehicle may display a trailer identification plate, which will be the only license identification required on the trailer. The $10 fee is a one-time charge as long as the trailer is owned by the applicant.

Vehicles licensed for gross weight — both commercial and non-commercial — may tow any regularly licensed trailer as long as the weight of the trailer plus its load is included in the gross weight license of the towing vehicle. Make sure your tow vehicle’s declared gross weight covers the combined weight of the truck, trailer, and animals before you leave the farm.

Important Note: If you are operating a farm vehicle and want to qualify for federal agricultural exemptions, your power unit must display a “FARM” license plate or you must carry a completed “Designation as a South Dakota Farm Vehicle” form, available at sdtruckinfo.sd.gov.

Homemade trailers exceeding 3,000 pounds are required to go through the rebuilt application process and inspection. Homemade trailers 3,000 pounds or less may request an assigned serial number from their county treasurer to begin the title application process. If you have built your own livestock trailer, do not skip this step — operating an untitled homemade trailer is a compliance violation.

For cross-border hauls, South Dakota has reciprocity agreements with neighboring states. South Dakota and Iowa have agreed that Sioux City, IA, and North Sioux City, SD are open cities for the movement of commercial vehicles licensed in either state, and Sioux Falls, SD is an open city for the movement of livestock via SD38 from the Iowa State Line directly to Sioux Falls, provided the vehicles bear an Iowa license and the movement is interstate in nature. Similar limited reciprocity exists with neighboring North Dakota for commercial vehicles operating within designated border zones.

Structural and Safety Standards for Livestock Trailers in South Dakota

A livestock trailer is only as safe as its physical condition. South Dakota follows federal and state standards that govern the structural integrity, lighting, and coupling equipment on any trailer pulled on a public highway.

All farm machinery, including animal-drawn vehicles, designed for travel at speeds of 25 mph or less on a public highway must display a slow-moving vehicle emblem. The emblem must be in good condition and be mounted in a clearly visible location on the rear of the vehicle. If your livestock trailer is towed at low speeds — for example, moving animals within a farm complex to a public road — this requirement applies to you.

Any vehicle requiring the slow-moving vehicle sign is prohibited from operating on public roads between one-half hour after sunset and one-half hour before sunrise unless it has a flashing or rotating warning light clearly visible to vehicles approaching from the rear.

• Trailer lighting must include functioning brake lights, turn signals, and running lights
• Safety chains or cables are required between the towing vehicle and trailer
• Breakaway braking systems are required on trailers above certain weight thresholds
• Reflective tape and rear conspicuity markings are required on commercial trailers
• The trailer hitch and coupler must be rated for the loaded weight of the trailer

Reflective tape must be applied along each side and across the rear of the trailer on extended-length semitrailers, and rear under-ride protection must be provided under certain conditions. While this requirement is specifically triggered for overlength trailers operating under a permit, it reflects the general principle that rear visibility and protection are mandatory for all trailers operating on South Dakota roads.

Pro Tip: Conduct a pre-trip inspection using a standardized checklist that covers all lighting, brakes, tires, hitch hardware, and trailer floors before every haul. Documented pre-trip inspections are your best defense if a roadside officer questions your trailer’s condition.

For nighttime operations involving oversized loads, nighttime operations require additional safety measures, such as reflective signs and lights, to ensure visibility and safety on the road. Even if your livestock trailer does not qualify as oversized, the underlying principle of enhanced nighttime visibility applies broadly under South Dakota highway law. You can review related animal transport and safety standards in South Dakota by reading about goat ownership laws in South Dakota, which touch on animal welfare standards relevant to livestock producers.

Size, Weight, and Load Limits for Livestock Trailers in South Dakota

Understanding South Dakota’s size and weight framework is critical for livestock haulers, because violations can result in fines calculated per ton-mile over the legal limit — and those costs add up fast on a loaded cattle trailer.

The maximum height for any vehicle, including load, is 14 feet. The maximum width of any vehicle is 102 inches (8 feet 6 inches). The maximum allowable length for semi-trailers without a permit is 53 feet. These three dimensions define the standard envelope your livestock trailer must fit within on South Dakota highways.

Dimension	Standard Legal Limit	Notes
Height	14 feet	Applies to vehicle and load combined
Width	102 inches (8’6″)	No width limit for farmer-owned vehicles on state highways during daylight
Semi-trailer length	53 feet	Permit required for 53–60 ft trailers
Max gross weight (Interstate)	80,000 lbs	Permit required above this threshold
Single axle max weight	20,000 lbs	Subject to tire width calculations
Tandem axle max weight	34,000 lbs	Axles spaced 96 inches or less apart

Vehicles hauling agricultural products from farm storage or livestock from a farm are given a tolerance of 5 percent more than the legal limits if operating within a range of 50 miles of the loading site. Such vehicles may not exceed any posted weight of any bridge or road. This tolerance does not apply during spring load restrictions and is not permitted on the Interstate Highway System. The fine or penalty applies to the portion of the load more than five percent above the legal limit.

Important Note: The 5 percent weight tolerance for livestock haulers does not apply on the Interstate Highway System and is suspended during spring load restriction periods. South Dakota’s spring thaw restrictions can go into effect any time after February 15 — check with the SD Highway Patrol Permit Office before hauling heavy loads in late winter or early spring.

Motor vehicles owned by farmers used to transport their own farm commodities or implements are exempt from width and height limitations on state highways. However, all oversize movements on the Interstate highway system require oversize vehicle permits.

If your trailer or load exceeds standard dimensions, single-trip permits are valid for three days and are required for transporting non-divisible loads that exceed size and weight limitations. These permits must be obtained before entering the state and are specific to the route and load being transported. You can use South Dakota’s online legal weight calculator at sdaps.sd.gov to verify your configuration before departure.

Ventilation, Flooring, and Animal Space Requirements in South Dakota

South Dakota law and federal regulations place real obligations on livestock haulers when it comes to animal welfare during transport. The condition of your trailer’s interior — its floor, its ventilation, and the space available to each animal — directly affects both the health of your animals and your legal compliance.

Ventilation is one of the most critical factors in livestock transport. Like humans, animals appreciate climate control. If you are transporting in the summer, make sure there is good airflow and ventilation throughout the transportation process. If you are transporting in the winter, do your best to close off large openings to the bitter cold while still leaving space for the animals to breathe.

Flooring in a livestock trailer must provide secure footing for animals throughout the journey. Slippery or deteriorated flooring causes injury, stress, and potential carcass damage — all of which represent financial losses in addition to animal welfare violations. Key flooring standards include:

• Non-slip flooring surfaces, typically achieved with grooved steel, aluminum, or rubber matting
• No holes, gaps, or protruding hardware that could catch hooves or cause lacerations
• Adequate drainage to prevent pooling of urine and waste
• Structural integrity sufficient to bear the full loaded weight of the animals

Adequate space per animal is required to prevent injury from crowding. Density standards vary by species, animal size, and trip duration, but the general principle is that animals must be able to stand in a natural position and not be crushed against pen dividers or trailer walls during transit.

Key Insight: The federal Twenty-Eight Hour Law applies to interstate livestock transport. The Twenty-Eight Hour Law states that livestock being transported for longer than 28 consecutive hours must be offloaded for at least five consecutive hours to receive feed, water, and rest. Plan your routes accordingly if you are hauling long distances across state lines.

Providing food and water for your livestock is crucial to its overall mental well-being. Depending on the species and how far you are traveling, it is important to be prepared for your animal. Carry water and feed supplies appropriate for the species and expected travel time, and build rest stops into your itinerary for extended hauls.

Pen dividers and interior partitions must be structurally sound and free of sharp edges. Cattle, hogs, and horses each have different behavioral characteristics during transport, and your trailer’s interior configuration should match the species being hauled. Mixed-species loads require secure separation to prevent injury. For more on South Dakota’s animal care standards, see the state’s backyard chicken laws and beekeeping regulations for additional context on how the state approaches animal welfare across species.

CDL and Driver License Requirements for Hauling Livestock in South Dakota

One of the most misunderstood areas of livestock transport law is exactly when a Commercial Driver License is required and when agricultural exemptions apply. Getting this wrong can result in an out-of-service order and significant fines.

All farmers are required to have a valid driver license for the vehicle they are driving. If a vehicle requires the driver to hold a Commercial Driver License, the driver — including farmers — must have a CDL with the proper class and endorsements attached.

However, farmers who operate a Covered Farm Vehicle within the size and geographic limitations are not required to have a CDL. To qualify as a Covered Farm Vehicle (CFV) and access this exemption, four conditions must all be met:

1. The vehicle must be registered as a farm vehicle and operated with state-issued farm plates.
2. It must be operated by the owner of a farm or an employee or family member of the owner.
3. It must be used to haul agricultural commodities, livestock, or machinery to or from a farm.
4. The vehicle must not be used in for-hire motor carrier operations, unless such operations are by a tenant pursuant to a crop-share farm lease agreement.

If the vehicle combination GVWR is 26,001 pounds or less, carriers may use the exemption anywhere they are operating in the U.S. For heavier vehicles, geographic restrictions apply — the exemption is generally limited to intrastate operations or within 150 air miles of the farm when operating interstate.

Common Mistake: Many livestock haulers assume their farm plates automatically exempt them from all CDL requirements everywhere they drive. If any one of the four Covered Farm Vehicle conditions is not met, the vehicle does not qualify as a covered farm vehicle and its operations would be subject to the Federal Motor Carrier Safety Regulations unless some other exemption applies. Hauling livestock for a neighbor for compensation, for example, can disqualify you from the CFV exemption entirely.

For seasonal workers and farm-service industry employees, South Dakota offers a pathway that falls between a standard driver license and a full CDL. Drivers who are seasonal employees of a farm-related service industry — such as custom harvesters, farm retail outlet suppliers, agrichemical businesses, and livestock feeders — are eligible for a Restricted Commercial Driver License. Applicants must have a good driving record for the two most recent years and must have held a valid driver license for one year.

A Restricted CDL is valid for one 180-day period or two 90-day periods within the calendar year. This is a practical option for operations that require commercial-level hauling during peak livestock movement seasons without committing to a full CDL year-round.

For commercial haulers operating interstate without farm exemptions, since February 7, 2022, first-time CDL applicants must complete Entry-Level Driver Training from an FMCSA-registered provider before taking CDL skills tests. This requirement applies to drivers seeking a new CDL or upgrading their CDL class. You can find more on how South Dakota handles animal-related legal frameworks — including how ownership and transport intersect — in the state’s leash laws and kennel zoning laws.

Passing Roadside Inspections With a Livestock Trailer in South Dakota

Roadside inspections are a reality for any livestock hauler operating on South Dakota’s interstates and major highways. Knowing what inspectors look for — and having your documentation in order before you leave home — is the most effective way to move through an inspection without delays or violations.

South Dakota operates commercial vehicle weigh stations at its interstate and international borders. These fixed inspection sites monitor all commercial traffic entering South Dakota for registration, taxes, size and weight restrictions, CDL requirements, and insurance compliance.

South Dakota uses weigh-in-motion technology and electronic screening systems — PrePass and Drivewyze — at these locations. If your vehicle is enrolled in PrePass or Drivewyze and has a clean safety record, you may receive a green light to bypass the weigh station entirely. Maintaining a strong safety score is one of the most practical ways to reduce inspection frequency.

When you are directed in for inspection, officers will typically check the following:

• Driver license class and endorsements (or CFV documentation if claiming farm exemption)
• Vehicle registration and trailer identification plate
• Medical certificate if a CDL is required
• Proof of insurance
• Vehicle weight versus declared gross weight license
• Trailer lighting, brakes, tires, and coupling equipment
• Animal welfare conditions inside the trailer
• Hours-of-service logs or ELD records (if applicable)

Pro Tip: Keep one physical or digital folder per vehicle containing all maintenance records, annual inspections, and driver vehicle inspection report (DVIR) history. Being able to produce documentation quickly at a roadside stop demonstrates professionalism and can prevent a routine check from escalating into a full-scale inspection.

Two documentation failures consistently result in out-of-service orders. An expired medical certificate causes the driver’s CDL to become invalid, and if an officer discovers it at a weigh station, the driver is placed out of service immediately. A vehicle operating with an expired annual inspection is an automatic violation. Track both expiration dates on a calendar and set reminders well in advance.

If a roadside inspection reveals that your vehicle does not qualify for CFV exemptions but you have been operating as though it does, the inspector can place the vehicle out of service. That means your truck does not move until the violations are corrected. If you are hauling livestock or perishable commodities, an out-of-service order can mean real financial losses beyond any fine.

For farm vehicles claiming the agricultural exemption on interstate hauls, the self-certification form from one state may not be immediately familiar to law enforcement in another, so carrying a copy of the federal regulation or FMCSA’s agricultural reference guide can smooth things over during an inspection. Download the FMCSA’s Agricultural Exceptions and Exemptions guide and keep a printed copy in your cab.

South Dakota’s Motor Carrier Services division of the Highway Patrol is the primary contact for questions about size, weight, and inspection requirements. You can reach them at 605-224-7364 or visit sdtruckinfo.sd.gov for the full Commercial and Agricultural Vehicle Handbook. Producers who also handle other regulated animals alongside their livestock operation may find it useful to review pit bull laws in South Dakota and hedgehog ownership laws for a broader picture of how South Dakota regulates animal ownership and transport across the board.

Staying compliant on every livestock haul in South Dakota comes down to preparation: the right registration on your trailer, a trailer that meets structural and safety standards, a load that stays within legal weight and size limits, animals that have adequate space and ventilation, a driver license that matches the vehicle being operated, and documentation that you can produce on demand at any weigh station. Get those six elements right, and your haul will move smoothly from loading to delivery.