Welcome to Missouri Roadways

Traffic Laws & Regulations

The information in this brochure has been prepared to assist residents and nonresident tourists of Missouri to become familiar with some of the traffic laws and regulations of our state. It is not intended to cover all aspects of the movement of motor vehicles on the highway. It is intended, however, to answer many of the general questions about operating a motor vehicle in Missouri.

Missouri highways are patrolled by troopers of the Missouri State Highway Patrol. The primary responsibilities of the Highway Patrol are to promote safety upon Missouri roadways and to enforce the traffic laws. The troopers are there to serve and protect you. We invite you to contact them for information or assistance.

Driver’s License

New Resident

If you have just become a resident of Missouri, you must make application for a Missouri driver’s license as soon as you physically take residence in the state, even if you have a valid license from another state, unless you are a commercial driver. Within 30 days after moving to this state, the holder of a commercial driver’s license must apply for a commercial driver’s license in Missouri.

Non-Resident

If you are not a resident of Missouri, and you have a valid driver’s license in your state, no Missouri driver’s license is required. However, no non-resident person under the age of 16 may operate a motor vehicle on Missouri highways.

Commercial Driver’s License (CDL)

The CDL is required if you transport hazardous materials that require placarding; transport 16 or more passengers including the driver; drive a vehicle with a gross vehicle weight rating (GVWR) or registered gross weight of 26,001 or more pounds; or drive combination vehicles with a gross combination weight rating (GCWR) or a registered gross weight of 26,001 or more pounds, provided the GVWR of the vehicle(s) being towed is in excess of 10,000 pounds.

Motorcycles

Traffic regulations that govern other motor vehicles in Missouri also apply to motorcycles. Motorcycle riders 26 or older, with proof of valid medical insurance, are not required to wear a helmet. All other riders are required to wear a DOT approved helmet. Persons operating a motorcycle or motortricycle upon the highway must possess a valid license with a motorcycle endorsement.

Speed Limits

Speed limits vary depending upon highway types and may vary upon the same highway. Speed limits, however, are posted. Obey the posted limits.

Minimum

The minimum speed limit on interstate highways is 40 mph. No vehicle shall be driven at such a slow speed as to impede or block the normal and reasonable movement of traffic on any highway.

Basic Rule

Every person operating a motor vehicle on the highways of this state shall drive the vehicle in a careful and prudent manner and at a rate of speed so as not to endanger the property of another, or the life or limb of any person, and shall exercise the highest degree of care. The maximum speed limit allowed is not lawful in situations that require a slower speed to comply with the basic rule (such as ice- or snow-covered roads).

Enforcement

State troopers use radar, aircraft, and patrol cars with calibrated speedometers to enforce the speed laws of Missouri. The maximum fine for speeding is $500 and/or six months in the county jail.

Vehicle Registration

If your vehicle has a valid license plate from your home state and you have established residency in Missouri, you may legally operate the vehicle on Missouri roadways for 30 days before being required to obtain a Missouri license plate.

Towing (Other Than Trailer)

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

Trailer Regulations

• Speed: The speed is regulated by the speed limit for the tow vehicle.
• Taillights: Each trailer must display (on the rear) two red taillights, two red reflectors, and a white license plate light. The reflectors may be incorporated in the taillights.
• 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: 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.
• Break-Away Switch: Every trailer is required to be equipped with brakes. The brakes shall be equipped with brakes of such character as to be applied automatically and promptly upon breakaway from the towing vehicle. Brakes must maintain application on the trailer for 15 minutes.
• Brake Lights and Directional Signals: These signals are required if visible signals cannot be given by arm and hand; or when the distance from the center of the top of the steering post to the left outside limit of the body, cab, or load exceeds 24 inches; or when the distance from the center of the top of the steering post to the rear limit of the body or load exceeds 14 feet.

Dimensions

• Width: Maximum width of a vehicle on all highways is 102 inches.
• Height: All vehicles traveling Missouri interstate and specially designated highways (plus a distance of 10 air miles therefrom) can have a maximum height of 14 feet; 13 1/2 feet on all other highways. Automobile haulers are allowed 14 feet on all highways.
• Length: The maximum length for a single motor vehicle, including load, is 45 feet; recreational vehicles may be 45 feet. For truck-tractor and semi-trailer units a maximum of 60 feet (except on interstate and designated highways plus 10 air miles therefrom, no overall length, but the trailer and load cannot exceed 53 feet). For all other combinations of vehicles the maximum length is 65 feet on the primary and interstate highways plus 10 air miles therefrom, otherwise 55 feet on all other highways.

Permits

• Reciprocity: Reciprocity permits must be in effect prior to entering the state. Contact Highway Reciprocity, 1320 Creek Trail Drive, Jefferson City, MO 65102.
• Fuel: Interstate Fuel Tax permits must be in effect prior to entering the state. Contact the Missouri Department of Revenue, Interstate Motor Fuel Tax Division, P.O. Box 893, Jefferson City, MO 65102-0893, (573) 751-2611.
• Over-Dimension: Over-dimension permits must be in effect prior to moving an over-dimension load upon Missouri highways. Contact the Missouri Department of Transportation, P.O. Box 893, Jefferson City, MO 65102-0893, 1-800-877-8499 or (573) 751-7100. Over-dimension load movements are restricted to daylight hours only, and movement is prohibited on weekends and legal holidays.

Hands-Free Law

All drivers on Missouri roadways may not:

• Hold or support a cell phone or other wireless device while driving. Drivers can use Bluetooth or voice-activated features while driving.*
• Manually type, write, send, or read any text-based communications on an electronic communication device.
• Watch, record, post, send, or broadcast a video or movie.

*Features include GPS and other hands-free apps.

Penalties: First conviction: up to $150 fine. Second conviction: up to $250 fine. Third conviction: up to $500 fine.

Seat Belts

Missouri law requires the operator and front seat occupants of all passenger vehicles to wear a properly adjusted and fastened seat belt. Children ages four to seven who weigh at least 40 pounds, but less than 80 pounds, and are less than 4’9” tall, must be secured in a child passenger restraint system or a booster seat appropriate for that child. Children ages eight to 16 who are at least 80 pounds or are taller than 4’9” tall must be secured by a vehicle safety belt. Children under four years of age must be protected by a child passenger restraint system (child safety seat) when transported in any motor vehicle other than a public carrier for hire.

Financial Responsibility Law & Traffic Crashes

If you are involved in a traffic crash in which a person is killed or injured, or in which property damage (including your own) exceeds $500 and one of the motorists does not have insurance and a settlement has NOT been agreed to by all parties, you are required to file a Missouri Motor Vehicle Accident Report Form (DOR-1140) with the Missouri Department of Revenue within 60 days from the date of the crash.

Missouri law requires the owner or operator of a motor vehicle involved in a traffic crash in this state on a roadway or parking lot open to the public to report the crash to the nearest police agency. Leaving the scene of a motor vehicle crash can be a felony violation.

Miscellaneous Information

• Rest Areas and Roadside Parks: These areas are provided throughout Missouri, and you are encouraged to use them. There are no costs or restrictions that prohibit units from staying overnight. Camping in a tent or on the ground generally is prohibited in these areas.
• Riding in an Unenclosed Pickup Bed: It is illegal for anyone under the age of 18 to ride in the unenclosed bed of a truck which is licensed for a gross weight of less than 12,000 lbs.
• Litter Laws: Throwing refuse of any kind, nature, or description on the highway is prohibited. The maximum fine is $1,000 for each offense.
• Abandoned Vehicle: Any vehicle left unattended on a highway right-of-way for 24 hours (10 hours in urban areas) may be towed to a place for safe keeping. Any vehicle impeding traffic may be towed immediately, at the expense of the owner.
• Studded Tires: Metal or carbide studded tires are not permitted April 1 to November 1 each year.
• Railroad Crossings: Drivers are required to stop within 50 feet but not less than 15 feet of a railroad crossing when an electric or mechanical signal is activated, when a crossing gate is lowered, or when a train is approaching.
• School Bus Law: When a school bus is stopped loading or unloading children, other motorists following or approaching the bus are required to stop. Those approaching a stopped school bus on the other side of a four-lane divided highway are not required to stop.
• Emergency Vehicle: Upon the approach of an emergency vehicle (from any direction) displaying red or blue lights and sounding a siren, motorists must drive as far to the right of the highway as possible and stop. They must remain stopped until the emergency vehicle has passed. Upon approaching a stationary vehicle displaying red or red and blue lights, or a stationary vehicle displaying lighted amber or amber and white lights, the driver of every motor vehicle shall proceed with caution and yield the right-of-way by making a lane change into a lane not adjacent to that of the stationary vehicle on a roadway having at least four lanes; or proceed with caution and reduce speed if changing lanes would be unsafe or impossible.
• Signaling: A signal by an arm and hand or electrical turn signal must be used when changing lanes or direction.
• Passing on the Right: Passing on the right is permitted on four-lane highways. The shoulders of the highway may not be used to pass another vehicle.
• Turns: Motorists are permitted to make a right turn on a red signal at an intersection after making a complete stop (except where signs prohibiting such a turn are posted).
• Following Distance: Commercial vehicles must maintain a 300-foot interval (pickup trucks are commercial vehicles in Missouri). Passenger vehicles must not follow another vehicle more closely than is reasonably safe and prudent.
• Weigh Stations: Commercial motor vehicles licensed for over 18,000 pounds are required to stop at all weigh stations.
• Outboard Motors: Visitors are not required to register outboard motors when vacationing in Missouri if the vacation time is not more than 30 days.
• Fuses, Flares, or Fire Extinguishers: These items are required for commercial vehicles.
• Bicycles: Are subject to most traffic regulations applicable to motor vehicles. Additional laws specify lights and reflectors if ridden after dark. Helmet use not required, but recommended.

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