Police have clarified exactly when drivers should merge lanes when two lanes converge into one on UK roads, confirming the technique known as "zip-merging" is the correct approach. Motorists who fail to follow the guidance could face a £100 fine and three penalty points for careless driving.
Almost every UK motorist will have encountered the scenario where two lanes merge into one, whether due to a permanent lane reduction or during roadworks on a motorway. Many drivers will have seen a long queue in the left-hand lane while the right-hand lane remains empty, and some will have felt frustration at motorists using the empty lane to sail past stationary traffic up to the merge point.
One driver from Cardiff said: "I'm not sure anyone knows for certain what the rule is. But judging from how frequently you get drivers in the left hand lane doing their best to stop you merging in from the right, I'd imagine most people think those wily right hand lane drivers are just trying to stitch them up and jump the queue."
Zip merging is the correct technique
The proper technique for merging when two lanes converge at a specific point is "zip-merging", according to WalesOnline. Rather than pulling into a single lane as soon as a lane closure is signposted, drivers should take turns merging one at a time at the actual point where one lane ends.
The method gets its name from the way the teeth of a zip come together and is widely regarded as an effective way to significantly reduce traffic build-up. The police, Highway Code, RAC and National Highways all agree on this approach.
Avon and Somerset Police stated that the method "helps make full use of the available road space" and added: "Problems tend to arise when drivers are unwilling to allow others to safely merge, or when motorists change lanes aggressively, without adequate observation, signalling or consideration for other road users."
Highway Code rule 134 and RAC advice
Highway Code rule 134 covers lane-merging by stating: "You should follow the signs and road markings and get into the lane as directed. In congested road conditions do not change lanes unnecessarily. Merging in turn is recommended but only if safe and appropriate when vehicles are travelling at a very low speed, e.g. when approaching road works or a road traffic incident."
National Highways offered similar guidance, stating: "By keeping both lanes in use until the merge point, congestion is minimised and journey reliability is improved."
The RAC concurred, stating: "When motorists encounter a lane closure on a motorway or dual carriageway, the majority of drivers follow the etiquette of moving over early, but this creates one long, slow line of traffic and a near-empty outside lane."
"While motorists on the inside lane might think they're doing the right thing, it can be more beneficial to continue using the open lane until the last minute, utilising all of the available road and then 'merging in turn' at the point at which the road narrows to a single lane," the RAC added.
Fine for incorrectly merging lanes
While drivers will not face a fine for joining the left-hand queue prematurely, or for using the empty lane up to the merge point, improper use of merger lanes could lead to a driving conviction, fine and penalty points. Attempting to block someone from using the less congested lane could result in prosecution for careless driving, with a fixed penalty of £100 and three points on the driver's licence.
National Highways said: "Dangerous, careless or inconsiderate driving can occur if a driver forces their way into traffic, deliberately obstructs other vehicles, or carries out manoeuvres which create a risk of collision."
If drivers encounter obstruction from someone who does not understand proper lane merging, they should avoid reacting with anger. Those with a dashcam fitted can submit footage to Operation Snap, a UK police scheme that enables members of the public to upload video evidence of suspected driving offences.
