Speed Limit Sign
The speed limit sign is a white rectangular sign showing the maximum legal speed in kilometres per hour for that section of road. Drivers must not exceed the posted number under normal conditions.
Last updated: April 4, 2026
Speed limit signs establish the maximum speed permitted by law under normal road and weather conditions. Driving above the posted limit is a Highway Traffic Act offence. Ontario uses a default speed limit system: 50 km/h in urban areas without a sign, 80 km/h on county roads, and 100 km/h on most provincial highways. Posted signs override these defaults.
Quick Facts
Type
Regulatory Sign
Shape
Rectangular
Colours
White background with black text
In this guide
What does the Speed Limit Sign mean?
Speed limit signs establish the maximum speed permitted by law under normal road and weather conditions. Driving above the posted limit is a Highway Traffic Act offence. Ontario uses a default speed limit system: 50 km/h in urban areas without a sign, 80 km/h on county roads, and 100 km/h on most provincial highways. Posted signs override these defaults.
What to do when you see it
Do not exceed the speed shown. During bad weather, heavy rain, snow, ice, or reduced visibility, you must reduce your speed below the posted limit to match conditions. The sign shows the maximum, not a target. Driving well below the posted limit is permitted as long as you are not obstructing traffic unreasonably.
Where you'll see it in Ontario
Speed limit signs are posted at the beginning of speed zones, after intersections where the speed changes, at school zones, construction zones, and whenever the legal speed differs from the provincial default. Watch for them when transitioning from highway to urban roads.
G1 test relevance
The G1 test includes questions on default speed limits: 50 km/h in areas with no posted sign in a city or town, and 80 km/h on roads outside cities and towns. Questions also test whether drivers know that posted school zone and construction zone speeds are mandatory reductions, not advisory.
Common mistakes drivers make
A common error is treating the speed limit as a floor rather than a ceiling, especially on highways where many drivers exceed the posted 100 km/h. Another mistake is failing to reduce speed during adverse weather. Driving at 100 km/h on an icy highway is dangerous and exposes drivers to careless driving charges even if they are at the posted limit.
Related Signs
School Zone Sign
The school zone sign marks the beginning of a reduced speed area near a school. In Ontario, the default school zone speed is 40 km/h or as posted, and applies during school hours and when children are present.
Learn moreConstruction Speed Limit Sign
The construction speed limit sign is an orange sign showing a reduced speed limit that applies within a construction zone. Fines for exceeding this limit are doubled when workers are present.
Learn moreMinimum Speed Sign
The minimum speed sign shows the slowest speed drivers are legally permitted to travel on that section of road. Driving slower than the posted minimum without a valid reason is an offence under the Ontario Highway Traffic Act.
Learn moreCommunity Safety Zone Sign
A community safety zone is a designated area around schools, playgrounds, or other places where children gather. All traffic fines for speeding, disobeying signs, and other offences are doubled inside these zones.
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