Traffic Lights & Signals
Solid and flashing lights, advance green arrows, and pedestrian signals.
Stop completely for red, prepare to stop for yellow, and treat green as permission to proceed only after yielding to whoever is already in the intersection.
A traffic light tells you when you may move, but it never removes your duty to check that the intersection is actually clear before you enter it.
Key facts
- A green light means you may go straight, turn left, or turn right, but only after yielding to vehicles and pedestrians already in the intersection.
- You may turn right on a red light after coming to a complete stop and confirming the way is clear, unless a sign specifically forbids it.
Read the solid colours
A red light requires a complete stop at the marked line, crosswalk, or intersection edge. A yellow light means the red is about to appear; you must stop if you can do so safely, and only proceed with caution if stopping would not be safe. A green light permits you to go straight, turn left, or turn right, but only once you have yielded to vehicles and pedestrians already in the intersection.
Yellow is a warning to prepare to stop, not a signal to speed up and beat the red: treating it that way is one of the most commonly cited errors among new drivers.
Turning at a light
A left-turn green arrow, shown together with a green light or on its own, gives you a protected turn. You may go even if oncoming traffic is also facing a left-turn arrow, since the conflicting movements are not released at the same time. A flashing green light or a left-pointing green arrow together with a full green light means you may turn left, go straight, or turn right from the correct lane.
Turning right on a red light is allowed in Ontario after a complete stop and confirming the way is clear of traffic and pedestrians, unless a posted sign specifically prohibits the turn at that intersection. Turning left on red is allowed only when moving from one one-way road onto another one-way road, again after a full stop.
Flashing signals and pedestrian control
A flashing red light is treated the same as a stop sign: come to a complete stop, then proceed only when it is safe. A flashing yellow light means proceed with caution: slow down and be ready to yield, but a full stop is not required if the way is clear. If the signal is dark because of a power failure, treat the intersection as an all-way stop.
A pedestrian signal operates alongside the traffic light and controls when people may cross, but it does not remove a driver’s duty to watch for pedestrians who are still completing a crossing when your light changes.
Common mistakes
- Entering an intersection on green when traffic ahead would trap your vehicle before you clear it.
- Accelerating through a yellow light instead of preparing to stop.
- Assuming a green arrow removes the need to scan the crosswalk for pedestrians.
- Treating a right turn on red as automatic without checking for a no-turn-on-red sign.
Check your understanding
1. You have a green light, but traffic ahead means you cannot fully clear the intersection before it changes. What should you do?
Wait until you can cross completely without stopping in the intersection: entering when you cannot clear it is prohibited even on a green light.
2. The traffic lights at an intersection are completely dark due to a power outage. How should you treat the intersection?
Treat it as an all-way stop: come to a complete stop and proceed using standard right-of-way rules with the other stopped vehicles.
3. When are you allowed to turn left on a red light in Ontario?
Only when travelling from one one-way road onto another one-way road, and only after coming to a complete stop and confirming the way is clear.
Related Ontario G1 guides
Official references
- Official MTO Driver's Handbook: Traffic lights
- Official MTO Driver's Handbook: Pedestrian signals
- Official MTO Driver’s Handbook: Driving through intersections
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