Traffic Lights

Chapter 17

Trafflic lights in UK

About half of all crashes occur at intersections. Obey the rules and drive carefully. Approach traffic lights at a speed that allows you to stop if the colour changes before you reach the intersection.

Try not to be caught in the middle of an intersections when the traffic lights change. You should stay on the approach side until you see a big enough gap in your lane on the other side.

Beyond the intersection is a traffic jam. Car A shouldn’t enter the intersection unless there’s a large enough gap on the other side

Red light - You must stop. Do not enter the intersection.

Amber light - You must stop, unless unable to do so safely.

Sometimes it’s not safe to stop if a driver is crossing as the light turns amber. You are then advised to continue driving through the intersection.

Green light - Enter the intersection and proceed carefully

A green, amber and red traffic light

A turning vehicle always has to give way to pedestrians who are crossing the road they are turning into, even if the pedestrian is not facing a green ‘walking figure’. Also give way to any vehicles using a bus lane, cycle lane or tramway from either direction.

Car A is facing a green light, but must still give way to car B and the pedestrians crossing the road

Where should you stop?

There are traffic lights with and without stop lines:

  • Traffic lights with stop line - you must stop just before the stop line.
  • Traffic lights without stop line - you must stop before the traffic light.

Green filter arrow

This indicates a filter lane only. Do not enter that lane unless you want to go in the direction of the arrow. You may proceed in the direction of the green arrow when it, or the full green light shows. Give other traffic, especially cyclists, time and room to move into the correct lane.

Turning right at traffic lights

Unless otherwise indicated:

  • give a right-turn signal
  • take up a position just left of the middle of the road or in the space marked for traffic turning right
  • leave room for other vehicles to pass on the left, if possible.
  • keep your wheels straight
  • wait for traffic to clear and then make a safe turn, or turn if you see a safe break in traffic

If you are waiting in a junction to turn right and the lights turn to amber or red, ensure you exit the junction as soon as safe. Don’t panic and force a dangerous turn, but turn as soon as oncoming traffic has dispersed. Do not remain within the junction!

Malfunctioning traffic lights

Due to errors in the system, traffic lights can sometimes not work at all. Proceed with caution and treat the situation as you would at an unmarked junction. In an unmarked junction, nobody has priority.

Box junctions

Rule 174: Enter a box junction only if your exit road is clear
Rule 174: Enter a box junction only if your exit road is clear

These have criss-cross yellow lines painted on the road. You MUST NOT enter the box until your exit road or lane is clear. However, you may enter the box and wait when you want to turn right, and are only stopped from doing so by oncoming traffic, or by other vehicles waiting to turn right.

At signalled roundabouts you MUST NOT enter the box unless you can cross over it completely without stopping.

Police directions

You must obey any direction from a police officer or other authorised person. They often give hand signals at intersections.

  • The woman is showing STOP hand signals.
  • The man is showing hand signals to beckon traffic on.

Take our full course with tests and theory

750+ exam-like questions

All you need to ace your test

Free trial

Ace your theory test, guaranteed