Police officer reveals the only time you’re allowed to undertake on the motorway

It is in the highway code

Skills such as entering via slip roads, maintaining a safe distance and remaining hyper-alert of your surroundings are crucial and it's essential to observe lane discipline and steer clear of undertaking.

The act of undertaking is when you overtake a vehicle on the left on the motorway and is generally discouraged by the Highway Code due to the heightened risk of accidents.

Sergeant Owen Messenger from Devon and Cornwall Police, Roads Policing Unit, recently posted an explainer video on the George's Car Media TikTok page offering clarity on when undertaking might be acceptable.

Sergeant Messenger explains: "You can't undertake on the motorway. The only time that you can undertake is when your lane is genuinely moving slower than the other lanes. That's generally when you're going through roadworks, or it's heavy traffic, or something like that."

He also explained why it's discouraged saying it's because 'people aren't expecting you' and since motorists often return to the left lane, their 'default position on the motorway', this can result in collisions.

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He continued: "Please don't undertake on the motorway, it's really really dangerous."

He also warned of the potential repercussions for drivers: "Well, it's just unnecessary isn't it. The default position [...] is to be in lane one, and if everyone stuck to the rules you wouldn't have everyone darting around all over the place."

According to Rule 268 of The Highway Code: "In congested conditions, where adjacent lanes of traffic are moving at similar speeds, traffic in left-hand lanes may sometimes be moving faster than traffic to the right. In these conditions you may keep up with the traffic in your lane even if this means passing traffic in the lane to your right. Do not weave in and out of lanes to overtake."

Undertaking might also be permissible during an average speed check where drivers are recommended to 'stay in lane'.

Under these circumstances, it could be safe to overtake a slower-moving vehicle on your right if your lane has a quicker pace.