Chapter 2: Speed Limits

Controlling a vehicle’s speed is one of the most critical aspects of safe driving. Understanding and obeying speed limits is not just about avoiding a ticket; it is about having enough time to perceive hazards, react appropriately, and bring the vehicle to a safe stop. Questions on Missouri’s statutory speed limits, the Basic Speed Law, and special zone rules are a core part of the driver’s license exam, ensuring new drivers know how to manage their speed for their own safety and the safety of others.

Missouri law establishes maximum speed limits for all roadways, but it also requires drivers to adjust their speed based on prevailing conditions. The posted speed limit is the absolute maximum allowed under ideal circumstances. A driver’s primary responsibility is to maintain a speed that is careful and prudent at all times.

The Basic Speed Law

The most fundamental rule regarding speed is the Basic Speed Law. This law requires that a driver must never operate a vehicle at a speed faster than is reasonable and proper for the existing conditions. This means a driver must slow down from the posted maximum speed limit when circumstances demand it.

Factors that require a reduction in speed include:

• Heavy traffic or congestion.
• Poor weather conditions such as rain, fog, snow, or ice.
• Roadways that are wet, icy, or slippery.
• Limited visibility at night or in bad weather.
• The presence of pedestrians, bicyclists, or slow-moving vehicles.
• Approaching and crossing intersections or railroad crossings.
• Driving on winding roads, through curves, or when approaching the crest of a hill.