Missouri Traffic Laws and Regulations

• The brochure provides information to help Missouri residents and tourists understand the state's traffic laws and regulations.
• It aims to answer common questions about operating a vehicle in Missouri.
• Missouri State Highway Patrol troopers patrol the highways.
• Their primary duties include promoting safety on roadways and enforcing traffic laws.
• Troopers assist and protect the public, and can be contacted for information.

Driver's License

• New Missouri residents must apply for a state driver's license as soon as they establish residency, even with a valid out-of-state license, unless they are commercial drivers. Commercial drivers have 30 days to apply for a Missouri commercial driver's license (CDL).
• Non-residents with a valid license from their home state do not need a Missouri driver's license.
• Non-residents under 16 cannot operate a vehicle on Missouri highways.
• A CDL is required for transporting hazardous materials that require placarding.
• A CDL is required For transporting 16+ passengers including the driver.
• A CDL is required For driving a vehicle with a GVWR or registered gross weight of 26,001+ pounds.
• A CDL is required For driving combination vehicles with a GCWR or registered gross weight of 26,001+ pounds, provided the towed vehicle(s) GVWR exceeds 10,000 pounds.

Motorcycles

• General traffic regulations apply to motorcycles in Missouri.
• Motorcycle riders 26+ with proof of valid medical insurance are not required to wear a helmet.
• All other riders must wear a DOT-approved helmet.
• Motorcycle operators must have a valid license with a motorcycle endorsement.

Speed Limits

• Speed limits vary by highway type and are posted.
• Drivers must obey posted speed limits.
• The minimum speed limit on interstate highways is 40 mph.
• Vehicles cannot be driven so slowly that they impede traffic flow.
• Drivers must operate vehicles carefully and prudently, at a speed that will not endanger people or property, exercising the highest degree of care.
• Speed limits can be lowered based on conditions, such as ice or snow.
• State troopers enforce speed laws using radar, aircraft, and calibrated speedometers.
• The maximum fine for speeding is $500 and/or six months in the county jail.

Vehicle Registration

• New Missouri residents with a valid license plate from their previous state can legally drive in Missouri for 30 days before needing to register their vehicle.

Towing

• Missouri law states that when motor vehicles are being towed by a towline they must not be separated more than 15 feet.
• In addition to the towline, a safety chain or device is required.
• When towing at night, lawful lights must be displayed on the tow vehicle and the vehicle being towed.
• The tow vehicle must display a valid license plate.
• License plates are not required on motor vehicles being towed.
• Tow bars are not required, but recommended, in Missouri.

Trailer Regulations

• Trailer speed is regulated by the speed limit for the tow vehicle.
• Each trailer must have two red taillights, two red reflectors, and a white license plate light on the rear.
• Safety chains (or an equivalent device) are required in addition to the primary coupling device, except for farm equipment, wreckers, fifth-wheel or gooseneck type vehicles, and vehicles being towed that are not required to be licensed.
• Trailer brakes are required on trailers coupled by a fifth wheel and kingpin, and on trailers hauling hazardous materials with a gross weight exceeding 3,000 pounds.
• Every trailer must have a break-away switch that automatically applies the brakes if it separates from the towing vehicle.
• Brakes must stay applied for 15 minutes in the event of a trailer breakaway.
• Brake lights and directional signals are required if visible signals cannot be given by arm and hand.
• Signals are also needed.
• Signals also need to be used when the distance from the center of the top of the steering post exceeds 24 inches to the left or 14 feet to the rear.
• This applies to single vehicles or combination of vehicles.

Dimensions

• The maximum vehicle width on all highways is 102 inches.
• The maximum vehicle height is 14 feet on Missouri interstates and designated highways (plus 10 air miles), and 13.5 feet on other highways.
• Automobile haulers are allowed a height of 14 feet on interstates.
• The maximum length is 45 feet for a single motor vehicle (including load) and recreational vehicles.
• For truck-tractor and semi-trailer units: 60 feet maximum.
• Trailers and their loads cannot exceed 53 feet on interstates and designated highways.
• For other combinations of vehicles: 65 feet on primary and interstate highways (plus 10 air miles), otherwise 55 feet.

Permits

• Reciprocity permits are required before entering the state; contact Highway Reciprocity at 1320 Creek Trail Drive, Jefferson City, MO 65102 for details.
• Interstate Fuel Tax permits are required before entering the state. Contact the Missouri Department of Revenue, Interstate Motor Fuel Tax Division, P.O. Box 893, Jefferson City, MO 65102-0893 or call (573) 751-2611.
• Over-dimension permits are required before moving an over-dimension load. Contact the Missouri Department of Transportation, P.O. Box 893, Jefferson City, MO 65102-0893 or call 1-800-877-8499 or (573) 751-7100.
• Over-dimension load movements are restricted to daylight hours only and prohibited on weekends and legal holidays.

Additional Regulations

• Missouri has no restrictions on people riding in a trailer or camper while in motion.
• Commercial vehicles must maintain a 300-foot following distance.
• Passenger vehicles must maintain a safe and prudent following distance.
• Commercial motor vehicles licensed for over 18,000 pounds must stop at all weigh stations.
• There are no costs or restrictions that prohibit units from staying overnight in rest areas and roadside parks that are provided throughout Missouri.
• Camping in a tent or on the ground is generally prohibited in rest areas.
• It is illegal for anyone under 18 to ride in the unenclosed bed of a truck which is licensed for a gross weight of less than 12,000 lbs.
• Littering on the highway is prohibited; the maximum fine is $1,000.
• Vehicles left unattended on a highway right-of-way for 24 hours (10 hours in urban areas) may be towed.
• Vehicles impeding traffic may be towed immediately.
• Towed vehicles are at the owner's expense.
• Metal or carbide studded tires are prohibited from April 1 to November 1 each year.
• Drivers must stop within 50 feet, but not less than 15 feet, of a railroad crossing when signals are activated, gates are lowered, or a train is approaching.
• When a school bus is stopped for loading/unloading, other motorists must stop.
• Those approaching a stopped school bus on the other side of a four-lane divided highway are not required to stop

Driving Considerations

• Upon approaching an emergency vehicle displaying red or blue lights and a siren, drivers must move to the right of the highway and stop until it passes.
• When approaching a stationary vehicle displaying red/blue or lighted amber/white lights, drivers should proceed with caution, yielding the right-of-way by changing lanes or reducing speed.
• A signal by arm/hand or electrical turn signal must be used when changing lanes/direction.
• Passing on the right is permitted on four-lane highways, but not on the shoulder.
• Motorists can make a right turn on a red signal after a complete stop, unless prohibited by signs.

Vehicle Requirements

• Visitors are not required to register outboard motors while vacationing in Missouri for up to 30 days.
• Fuses, flares and fire extinguishers are required for commercial vehicles.
• Bicycles must follow traffic regulations.
• Lights and reflectors are required for bicycles ridden after dark.
• Helmet use on bicycles is not required, but recommended.

Hands-Free Law

• Drivers on Missouri roadways cannot hold or support a cell phone or other wireless device while driving.
• Drivers must use Bluetooth or voice-activated features for hands-free operation.
• Manually typing, writing, sending, or reading text-based communications is prohibited.
• Watching, recording, posting, sending, or broadcasting videos or movies is prohibited.
• First conviction: Up to $150 fine
• Second conviction: Up to $250 fine
• Third and subsequent convictions: Up to $500 fine

Safety Regulations

• Missouri law requires operators and front seat passengers to wear seat belts.
• Children ages four to seven (weighing 40-80 lbs, under 4'9" tall) must use a child passenger restraint system or booster seat.
• Children ages eight to 16 (at least 80 lbs or over 4'9" tall) must be secured by a vehicle safety belt.
• Children under four must be protected by a child passenger restraint system (child safety seat).

Financial Responsibility Law

• If involved in a traffic crash with injuries/death or property damage exceeding $500 (and lacking insurance), a Missouri Motor Vehicle Accident Report Form (DOR-1140) must be filed with the Missouri Department of Revenue within 60 days.
• Failure to report may lead to driving privilege suspension.
• The DOR-1140 form can be obtained from the investigating officer or the Missouri Department of Revenue's website.
• The form can be filled out online.
• All traffic crashes must be reported to the nearest police agency.
• Leaving the scene of a motor vehicle crash can be considered a felony violation.

Contact Information

• Missouri State Highway Patrol Emergency Highway Assistance: 1-800-525-5555 or cellular *55 (for emergencies only: crashes, medical emergencies, intoxicated drivers, reckless driving, vehicle problems, hazardous spills, or criminal activity).
• Emergency TDD number: 1-800-525-7559.
• Missouri Automated Road Condition Report: 1-888-275-6636.