Changing Lanes

There are times when you will need to move from one lane to the other – this might be to turn at a junction or to overtake another vehicle or because a lane is closed. Here are some thoughts on how to do that safely.

Identifying the need and collecting information are crucial to the task of changing lanes. You need to recognise there is a need or opportunity to change lanes early so that you have time to make all the necessary checks and you need to collect up to date information throughout – there is a chance that you will have to ‘abort the manouevre’ and stay in the lane you are in.

The Highway Code stresses the need to check your mirrors before any change of speed or direction. It is probable that you will be doing both when you change lanes, therefore use your mirrors early. If you identify a situation when you might want to change lanes start checking and keep checking those mirrors (always the centre one and the mirror on the side you wish to move toward). Problems can occur when people do not look carefully enough before moving over so do take time to look well, including a quick over the shoulder check if necessary.

Rule 133

If you need to change lane, first use your mirrors and if necessary take a quick sideways glance to make sure you will not force another road user to change course or speed. When it is safe to do so, signal to indicate your intentions to other road users and when clear, move over.


Again the Highway Code urges all road users to signal their intentions to others clearly and in a timely fashion. If you are changing lanes it is important to tell other people that – especially if you will be moving in front of others who are travelling at speed (e.g. on dual carriageway). Give you signal early enough that others will see and have time to act. Indicating and almost immediately moving over does not give others time to see and process and act on your signal. Surprising other road users is never a good idea so give time for others to react to your indicator. The Highway Code also points out that signalling does not give you the right to move out – you must ensure the space you move into is large enough that you will not be causing a problem to other road users.

There is the possibility in slow-moving queues that you will need to indicate before you can see a safe gap, i.e. you need to tell others that you wish to move over and then you wait until someone in the other lane is kind enough to create some space for you to do so (Remember to look out for people doing this when you are driving and where it is safe to do so allow them to move over). In most situations however you are best to leave the indication until you see a potential gap to move into.

Your position when changing lanes is bound up with the need to collect information and work out which lane you want to be in and with timing your movement. Leaving a change of lane until “the last minute” and thereby not being able to move over and prepare for what is happening next is just asking for trouble: Use road markings and signs to help you choose the lane you want in good time and start looking for a safe opportunity to move as early as possible. If you cannot see the road markings until late and it is safe to move over then do so but if it isn’t safe to move over then you may need to go the ‘wrong way’ (if at a junction) or stop (if your lane is closed or comes to an end) and wait for a safe gap to move out. It may be in some situations that a slight adjustment of your position is needed in order to get a better view of what is happening so that you can make a decision about if or when you change lanes. For example, in a queue of traffic the vehicles in front and behind can obscure your view of what is happening – if you move over so that you are to the edge of your lane you will be able to see farther ahead and behind.

Where there are queues and especially where two lanes become one (merge) I find it works best when drivers let one car in at a time – this keeps both lanes moving and prevents people acting out of frustration. The Highway Code refers to this as merging in turn i.e. one at a time, taking turns. The best way to encourage this is to maintain a slow and steady space and as you approach the place where vehicles need to move over ensure the space in front of you is large enough for a vehicle to move into. If you end up stopping you could find several cars move over before you get moving again and if you do not leave a big enough gap then drivers are not likely to move over. When you are the one hoping to move over then look for drivers who are putting the above into practise so that you can take the opportunity they are presenting.


Rule 127

A broken white line. This marks the centre of the road. When this line lengthens and the gaps shorten, it means that there is a hazard ahead. Do not cross it unless you can see the road is clear and wish to overtake or turn off.


Rule 128

Double white lines where the line nearest to you is broken. This means you may cross the lines to overtake if it is safe, provided you can complete the manoeuvre before reaching a solid white line on your side. White direction arrows on the road indicate that you need to get back onto your side of the road.

Rule 129

Double white lines where the line nearest you is solid. This means you MUST NOT cross or straddle it unless it is safe and you need to enter adjoining premises or a side road. You may cross the line if necessary, provided the road is clear, to pass a stationary vehicle, or overtake a pedal cycle, horse or road maintenance vehicle, if they are travelling at 10 mph (16 km/h) or less.

Laws RTA 1988 sect 36 & TSRGD regs 10 & 26

Rule 134

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. It is not recommended at high speed.

 It is through changing your speed and gear that you create time for yourself. It is important therefore that you judge your speed according to the situation and plan out what you need to do and when. For example, if you are wishing to change lanes in order to overtake a slower moving vehicle you will need to maintain enough speed and power to move out and get passed whilst also staying slow enough to remain a safe distance behind the slower vehicle whilst you make the necessary checks and find a safe opportunity to overtake. If approaching a queue of traffic you may need to be significantly slowing down but choosing a gear that allows you to gain speed quickly once you have moved into the other lane.

 Some situations will require good judgement as you lookassessdecide and act. If you are moving at great speed or there is little space available then you will need to ensure you have made a good decision and act on it in a timely fashion. Always in driving, if in doubt, wait. In other situations, changing lanes can be a very simple process. The videos on this page will take you through various  scenarios and as you get experience in different situations I trust you will manage a change of lanes with confidence and consideration.