When is it permissible to drive in the left lane of a highway?

Driving in the left lane of a highway is permissible primarily when overtaking another vehicle. This practice is rooted in the design and intention of multi-lane roads, where the left lane is typically reserved for faster-moving traffic and passing.

Using the left lane for overtaking allows for smoother traffic flow and ensures that vehicles can pass safely without disrupting the movement of others in the right lane, which is generally meant for slower vehicles or those traveling at a consistent speed. This rule promotes safety by reducing the potential for accidents that could occur from abrupt lane changes or interactions between vehicles moving at different speeds.

While there might be instances where driving in the left lane is allowed, such as during periods of light traffic or when directed by road signs, the primary and most recognized purpose remains overtaking. That ensures that drivers use the left lane only when it serves its intended function and maintains an orderly traffic environment.