Mississippi's primary keep-right and left-lane rule is found in Mississippi Code §63-3-603.
A vehicle traveling at less than the normal speed of traffic under the existing conditions generally must be driven in the right-hand lane available for traffic, or as close as practicable to the right-hand curb or edge of the roadway.
This slower-traffic requirement does not apply when the driver is overtaking and passing another vehicle traveling in the same direction or when preparing for a left turn at an intersection or into a private road or driveway.
Mississippi also has a stronger rule for multilane roads. A vehicle generally may not be driven in the outermost left lane of a roadway with two or more lanes moving in the same direction unless the driver is overtaking and passing another vehicle, the right lanes are closed for construction or repair, the right lanes are unsafe or impassable, or the driver is preparing to exit the roadway on the left.
The law also specifically prohibits continuously driving in the outermost left lane when doing so impedes the flow of other traffic.
Mississippi therefore goes beyond a traditional slower-traffic keep-right rule by directly restricting ordinary use of the far-left lane on multilane roads.
Exceptions
- Overtaking and passing another vehicle traveling in the same direction.
- Preparing for a lawful left turn or left-side exit.
- The right lane or lanes are closed because of construction or repair.
- The right lane or lanes are in disrepair, impassable or otherwise unsafe.
- Following official signs that designate another lane for traffic.
Penalties
A violation of Mississippi's outermost-left-lane restriction under §63-3-603(2) is punishable by a fine of not less than $5 and not more than $50.
Other keep-right or passing violations may be subject to different penalties depending on the specific provision charged.
Official Source
Mississippi Code §63-3-603 - Driving on Roadways Laned for Traffic
Last verified: October 11, 2026