One Way Sign
The one way sign indicates that traffic on that road travels in only one direction. All vehicles must travel in the direction shown by the arrow, and driving against the arrow is illegal.
Last updated: April 4, 2026
A one way sign means all lanes on that road carry traffic in a single direction. There is no oncoming traffic coming toward you. The sign is always black with a white directional arrow. One-way streets are common in downtown Toronto, Vaughan city centres, and parking structures. Travelling against a one-way means driving directly into oncoming traffic.
Quick Facts
Type
Regulatory Sign
Shape
Rectangular
Colours
Black background with white text and arrow
In this guide
What does the One Way Sign mean?
A one way sign means all lanes on that road carry traffic in a single direction. There is no oncoming traffic coming toward you. The sign is always black with a white directional arrow. One-way streets are common in downtown Toronto, Vaughan city centres, and parking structures. Travelling against a one-way means driving directly into oncoming traffic.
What to do when you see it
Travel only in the direction shown by the arrow. When turning onto a one-way street, you may turn into any lane that is safe and legal to use. When turning off a one-way street, you may turn from the lane closest to the direction of travel. Check for the one-way sign when entering any unfamiliar urban street.
Where you'll see it in Ontario
One-way signs are most common in urban grids, downtown business areas, parking garage exits and entrances, hospital and campus driveways, and at some highway interchange ramps. They are always placed at the entry point of the one-way section.
G1 test relevance
The G1 test asks about turning onto one-way streets. When turning left onto a one-way from a two-way road, you must turn into the leftmost available lane. When turning right onto a one-way, you must use the rightmost lane. These rules differ from normal two-way street turning rules and are a frequent test question.
Common mistakes drivers make
Turning onto a one-way street and drifting into the wrong lane is a common error. Another mistake is attempting to turn left from a one-way street from the wrong lane, or not checking whether the street you are turning onto is one-way before making your turn.
Related Signs
Do Not Enter Sign
The do not enter sign is a red circular sign with a white horizontal bar that prohibits all vehicles from entering a road or lane in that direction. It is typically posted at exit ramps and one-way street entrances.
Learn moreWrong Way Sign
The wrong way sign is a red rectangular sign that tells drivers they are travelling in the wrong direction on a road. It is typically posted past the do not enter sign to give a second warning to drivers who have entered against the flow of traffic.
Learn moreKeep Right Sign
The keep right sign instructs drivers to stay to the right side of a traffic island, obstruction, or divided road median. It directs traffic flow at road splits and median openings.
Learn moreTwo-Way Traffic Sign
The two-way traffic sign warns drivers that they are leaving a one-way road and entering a section where traffic travels in both directions. Drivers must adjust their position to the right lane.
Learn moreReady to Pass Your G1 Test?
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