Whilst the traffic light system in the UK might feel straightforward, there are plenty of exceptions to the rule and a few misconceptions too. We’re here to help answer your common questions and make sure you don’t get in any driving bother when you approach traffic lights.
What do traffic lights do?
Traffic lights are in place to help control the flow of traffic and make junctions safer. They can help make busy crossings easier to navigate, especially where there are multiple points of access and pedestrian crossings in the mix too. Whilst traffic lights are automated, it’s important to continue to use your own assessment of whether it’s safe to go.
Traffic light sequence in the UK
In its purest sense, the traffic light sequence is straightforward:
Red → Red and Amber (although this could be flashing amber) → Green → Amber → Red. Repeat.
Whilst the sequence feels simple, there are some important rules that you need to follow to keep in line with the law.
Red light
When a traffic light turns red you need to come to an immediate stop. ‘Running a red light’ is a prosecutable offence as it puts other drivers in immediate danger.
It’s important that you approach traffic lights with caution and at a sensible speed, mindful that they may change at any time. As the light turns red, you need to ensure that you avoid braking too hard or too suddenly as this too can create collision risks for any drivers behind you.
If you go through a red light and are caught by the police, you could be fined £100 and receive three points on your licence. Traffic lights at many busy junctions feature traffic light cameras which will automatically photograph and issue fines for any drivers caught advancing when the lights change red.
Motoring offences come with their own implications such as higher car insurance costs later down the line.
Amber light
When a traffic signal light turns amber, it means that it is time to stop.
Going through an amber light is not something you’ll be fined for, but as amber does not mean go, you are expected to proceed with caution. There may be scenarios where it is safer to cross the threshold than it is to brake suddenly, especially if doing so might create a collision for drivers behind.
However, if you see red and amber lights together, that means prepare to go.
Flashing amber lights
Flashing amber lights indicate that you need to proceed with caution – flashing amber lights will often appear at pedestrian crossings and some level crossings to give others more time to cross.
Green light
Unanimously, green means go and indicates that it is safe to drive through the light.
Who has priority when traffic lights are out of order?
If there aren’t any temporary traffic lights in place for when the usual traffic lights are out of order, then you should approach the junction as you would a four-way stop. This means treating the situation in the same way that you would an unmarked junction, which means giving way to whoever arrived first.
There isn’t necessarily a ‘priority’ of way in this case, but it is important to check all exits and ensure it is safe to go before crossing the threshold. For more information on this, you can refer to the highway code.
Traffic lights and emergency service vehicles
All emergency service vehicles with flashing blue lights are permitted to pass through red lights. This exception to the rule means that it’s really important you approach all traffic lights, regardless of their colour, with caution, making sure to check left and right before proceeding.
Frequently asked questions – traffic lights
Where do you stop at traffic lights?
If the light is red, you must stop at the traffic lights behind the thick white line which indicates ‘STOP’.
Do all traffic lights have cameras?
No, not all traffic lights have cameras. Where cameras are installed, they are in place to monitor traffic flow, enforce traffic regulations and also detect any traffic violations.
When were traffic lights invented?
The very first ‘traffic lights’ were installed outside the Houses of Parliament in 1868 by a British railroad engineer, John Peake Knight. Repurposing the concept from the rail network, gas traffic lights were installed to signal when it was safe for horse carriages to pass safely. Whilst these gas versions came with some hazardous outcomes, the first electric traffic signals were brought about in 1912 in Salt Lake City.
Motoring laws can often feel complex, we have plenty of guides to help you navigate the world of driving on UK roads. From new driving laws to parking on single yellow lines, what to do if you’re in a car accident and more tips on understanding warning lights, find plenty of interesting information and advice on our blog.