Louisiana speed limits and key traffic laws

By the end of this topic you can

• You can state Louisiana's default speed limits for different types of road.
• You can explain the basic speed rule and why minimum speeds exist.
• You can explain the rules for school zones and work zones.
• You can say when passing is illegal.
• You can apply the school bus and move over laws.

What you need to know and understand

• Unless a lower limit is posted, the general maximum on Louisiana highways is 55 mph.
• The default limit is 70 mph on interstates and other controlled-access highways and 65 mph on multi-lane divided highways without full access control. The state can post different limits in speed zones.
• Interstates have posted minimum speeds, and you must not drive so slowly that you hold up traffic.
• School zone speed limits marked 'when flashing' apply only while the lights flash.
• Traffic fines are doubled in highway construction zones.
• Stop at least 30 feet from a school bus loading or unloading children, whether you are behind it or meeting it, unless a barrier or median separates you.
• Headlights must be on from sunset to sunrise and whenever you need your windshield wipers.
• Drag racing or any speed contest on a public road is illegal.

Default limits at a glance

Higher posted limits exist on some rural interstates, and lower ones are common in towns. Always obey the sign in front of you.

• Most highways: 55 mph unless posted lower.
• Multi-lane divided highways with partial or no access control: 65 mph.
• Interstates and controlled-access highways: 70 mph.
• Residential, business and school areas: lower limits are posted, so watch for the signs.

Passing and lane use

Louisiana expects traffic to keep right except to pass or turn left, and a slower vehicle must use the right lane. You must finish a pass before coming within 100 feet of an oncoming vehicle.

• Do not pass when a hill or curve blocks your view.
• Do not pass when a solid yellow line is on your side.
• Do not pass within 100 feet of an intersection, railroad crossing, bridge or tunnel.
• Never pass on the shoulder.

School buses and stopped emergency vehicles

School buses switch on flashing yellow lights 100 to 500 feet before a stop, then red lights and a stop arm. Stop at least 30 feet away and wait until the bus moves. Traffic on the opposite side does not have to stop on a road split by a ditch, grassy median or barrier, or on four- or five-lane roads divided by a two-way left-turn lane. On a two-lane road with a center turn lane, everyone stops.

Under Louisiana's move over law, when you approach a stopped emergency vehicle on a road with two or more lanes in your direction, move to a lane not next to it if you safely can. If you cannot, slow down to a safe speed. Since August 1, 2026 (Act 234), the same duty also applies when you pass a disabled or broken-down vehicle showing hazard lights or other warning signals. The deeper guide on this site, learning to drive in Louisiana, covers more state laws.

Common mistakes

• Driving at the posted limit in heavy rain or fog. The basic speed rule can make that illegal.
• Forgetting to slow in a school zone when the lights are flashing.
• Cruising in the left lane. Louisiana law keeps slower traffic to the right.
• Passing a school bus on a four-lane road with no barrier. Both directions must stop there.

Test yourself: Louisiana speed limits and key traffic laws

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

Go deeper

• How to Get a Driver’s License in Louisiana
• Louisiana 6 Hour Pre-Licensing Course for Adult Drivers
• Louisiana Bioptic Driving