Missouri speed limits and key traffic laws

By the end of this topic you can

• You can state Missouri's default speed limits for each type of road.
• You can explain the minimum speed on interstates.
• You can say when you must stop for a school bus and when you need not.
• You can describe what to do when passing a stopped emergency or highway vehicle.

What you need to know and understand

• Unless signs say otherwise, the limit in any city, town or village is 25 mph.
• Default maximums are 75 mph on rural interstates and freeways, 65 on rural expressways, 60 on urban interstates and other non-urban roads, and 55 on lettered roads.
• Senate Bill 1408 raised the rural interstate and freeway default from 70 to 75 mph from August 28, 2026, but the posted limit is treated as the legal limit, so obey the signs.
• On interstates you may not drive slower than 40 mph in normal conditions.
• Speeding or passing in a work zone on state roads carries a minimum $250 fine for a first offense and $300 for a later one, on top of other fines.
• A speed limit is the maximum in ideal conditions; you must slow down for weather, curves and traffic.

Missouri default limits

Use these figures when no sign tells you otherwise. Cities and the state can set higher or lower limits for safety, so read every sign.

• Rural interstates and freeways: 75 mph (raised from 70 on August 28, 2026; always follow the posted sign)
• Rural expressways: 65 mph
• Interstates, freeways or expressways in urbanized areas: 60 mph
• Other roads outside urbanized areas: 60 mph
• Lettered roads: 55 mph
• Cities, towns and villages: 25 mph

School zones, work zones and school buses

Obey the lower school-zone limit when lights are flashing or children are present. In work zones, slow to the posted work zone limit and follow flaggers.

A school bus shows flashing amber lights about 500 feet before it stops. When its red lights flash and stop arm is out, traffic in both directions must stop on a two-lane road. You do not have to stop if you are going the other way on a road with four or more lanes or on a divided highway, or when the bus is in a school loading zone where children do not cross. Stay stopped until the bus moves or the driver signals you on.

The Move Over law

When you approach a stopped emergency vehicle showing red or red and blue lights, slow down and, on a road with at least two lanes in your direction, move to a lane not next to it if you can do so safely. If you cannot change lanes, slow down to a safe speed and pass with care. Missouri also extended this protection to stopped vehicles showing amber or amber and white lights, such as highway department and utility trucks.

Common mistakes

• Driving at the limit in rain or fog. The limit is for ideal conditions only.
• Assuming every rural interstate is now 75 mph. Follow the posted sign.
• Passing a stopped school bus on a two-lane road.
• Staying in the lane next to a stopped patrol car when the next lane is free.

Test yourself: Missouri speed limits and key traffic laws

Answer each question, then read the explanation. Questions come in a random order each time.

Go deeper

• Learning to Drive in Missouri
• Missouri 40-Hour Supervised Driving Requirement
• How to Get a Missouri Driver’s License as an Adult