Traffic lights
Understanding traffic lights, directional arrows and special lights for crossing intersections safely.
Updated 13 June 2026
The role of traffic lights
Traffic lights regulate traffic at intersections. They alternate the right of way between the different flows of vehicles and protect pedestrians. Even when the light is green, the driver must remain vigilant and ensure the intersection is clear before entering it.
Traffic lights are found at junctions in towns and outside built-up areas, but also at the entrance to certain tunnels, at level crossings or near roadworks zones. Pedestrian lights work in coordination with vehicle lights: when the pedestrian light turns green, vehicles must be stopped.
Traffic lights override priority signs. When the lights are working, they determine the order of passage.
The three colours and their meaning
The green light allows you to proceed, provided the intersection is clear. Never enter if vehicles are blocked on the other side: you risk being stuck in the middle of the junction and blocking cross-traffic when their light turns green.
The amber light (steady yellow) requires you to stop, unless you are too close to the light to brake safely. Its role is to prepare the transition to red. Warning: accelerating to 'get through before the red' is an offence frequently punished with a 135-euro fine and 4 penalty points.
The red light requires an absolute stop. You must come to a standstill before the stop line. If there is no line, stop before the pedestrian crossing or at the level of the light. It is forbidden to pass a red light, even if the cross-road appears empty.
Common exam trap: a green light does not oblige you to go. If a pedestrian is still on the crossing or the intersection is congested, you must wait even with a green light.
Running a red light results in a 135-euro fine and 4 penalty points. In the event of an accident, the criminal consequences are even more severe.
The stop line
The stop line is a road marking indicating the exact point where you must stop at a red light. It is often set back from the pedestrian crossing to leave a safety space for pedestrians crossing. Never pass it when the light is red or amber.
If no stop line is drawn, always stop before the pedestrian crossing. If no crossing is present, position yourself level with the light.
Arrow-shaped lights
An arrow-shaped light applies only to the direction indicated. If the right arrow is red but the circular light is green, you may continue straight ahead or turn left, but not right. Each arrow acts as an independent light for its direction.
A flashing amber arrow (often to the right or for cyclists) permits passage in the indicated direction, but you must give way to all users already engaged, particularly pedestrians. This device is notably used to allow cyclists to turn right at a red light, indicated by a small triangular sign beneath the light.
An additional flashing light showing 'BUS' allows buses to pass even when the main light is red. As a motorist, this does not concern you: remain stopped.
Flashing lights
A flashing yellow light on its own (instead of a normal traffic light) signals a dangerous spot. You may pass but with great caution and reduced speed. The usual priority rules then apply: priority to the right, signs, road markings. It is often encountered at night, when traffic is light and normal three-colour operation is no longer necessary.
A flashing red light requires an absolute stop. It is found notably at level crossings and at the entrance to certain reserved lanes.
Out-of-service lights: when the lights are no longer working, apply the priority sign present at the intersection. Without a sign, priority to the right applies.
Lane allocation lights and repeater
Lane allocation lights are positioned above the lanes in tunnels, at toll booths and on bridges. A red cross prohibits the lane, a green arrow permits it, and an amber arrow requires you to move over in the indicated direction.
The repeater is a small light placed at the back of a traffic light. It lights up red to inform users approaching from the opposite direction that vehicles on the other side are stopped.
Traffic officers
A police officer's gestures override traffic lights and signs. Officer seen from the front or back (or arm raised): stop required. Officer seen from the side: passage permitted. Up-and-down gestures: slow down. Circular gestures: speed up.
Even if the light is green, an officer raising their arm requires you to stop. Their instructions always take precedence over signage.
Recap
- Green light: passage permitted if the intersection is clear.
- Steady amber light: stop required unless braking is dangerous.
- Red light: absolute stop before the stop line or pedestrian crossing.
- Out-of-service lights: follow the sign; without a sign, priority to the right.
- Directional arrows apply only to the indicated direction.
- The flashing amber arrow permits passage with giving way.
- An officer's gestures always take precedence over lights and signs.
- A flashing red light requires an absolute stop (level crossings, reserved lanes).
Test yourself
At a steady amber light, what should you do?
- ○Accelerate to pass before the red
- ✓Stop unless stopping is dangerous
- ○Continue at the same speed
- ○Reverse to let pedestrians pass
Correct answer : Stop unless stopping is dangerous
When traffic lights are out of service, what rule applies in the absence of a sign?
- ○First to arrive goes first
- ○All vehicles stop
- ✓Priority to the right
- ○Pedestrians go first
Correct answer : Priority to the right
Sources: Sécurité routière (securite-routiere.gouv.fr) and service-public.fr.