Western Australia speed limits and key road rules

By the end of this topic you can

• You can name the default speed limit in a built-up area and outside one.
• You can apply the 100 km/h learner cap on faster roads.
• You can slow to 40 km/h in school zones at the right times.
• You can pass a stopped emergency or breakdown vehicle safely and legally.
• You can describe the penalties for speeding in WA.

What you need to know and understand

• The default limit in a built-up area is 50 km/h unless a sign shows otherwise.
• Outside built-up areas with no speed signs, the WA default limit is 110 km/h.
• Learner drivers must never exceed 100 km/h. Provisional drivers may drive up to 110 km/h where that is the limit.
• School zones are 40 km/h during the morning and afternoon times shown on the school zone signs on school days.
• You must pass a stationary incident response vehicle with flashing lights at no more than 40 km/h (Slow Down, Move Over, or SLOMO).
• On roads with a limit of 90 km/h or more, or with Keep Left Unless Overtaking signs, you must not stay in the right lane unless an exception applies.
• On a freeway you must not drive more than 20 km/h below the limit unless conditions require it.

WA's speed limits at a glance

Temporary limits at roadworks and events carry the same legal weight as normal limits, even if you cannot see any workers.

• Built-up area with no sign: 50 km/h.
• Open road with no sign: 110 km/h.
• School zones in operation: 40 km/h.
• Passing a stationary police, ambulance, fire, tow truck, breakdown or Main Roads incident vehicle with flashing lights: 40 km/h.
• Learner drivers, vehicles towing caravans or trailers, and some heavy vehicles: 100 km/h maximum.

SLOMO: passing a stopped incident vehicle

Hazard lights or indicators alone do not count as flashing warning lights, but if you are unsure, treat the vehicle as an incident response vehicle.

1. Approach at a safe speed and be ready to stop.
2. Slow to no more than 40 km/h, whichever lane you are in.
3. If the vehicle is in your lane on a multi-lane road, move to another lane if it is safe.
4. Leave as much space as you safely can, ideally a full lane.

What speeding costs

For cars, DTMI lists fines from $100 for up to 9 km/h over, through $200 and 2 demerit points for 10 to 19 km/h over, up to $1,200 and 7 points for more than 40 km/h over. Points are doubled in holiday periods. Under WA's anti-hoon laws, driving 45 km/h or more over the limit can lead to a reckless driving charge, and racing or burnouts can see your car impounded. For learners and P platers, a single speeding offence can push you close to the novice demerit limit. Our guide to country driving in WA covers open-road speed choices.

Common mistakes

• Driving at 110 km/h as a learner because the sign allows it. Learners are capped at 100 km/h.
• Forgetting school zone times during term. Watch for the signs and slow to 40 km/h.
• Rushing past a stopped tow truck with flashing lights. Slow to 40 km/h and move over if you can.
• Sitting in the right lane on a 100 km/h road. Keep left unless overtaking or another exception applies.
• Treating the limit as safe in rain, fog or heavy traffic. Slow down to suit the conditions.

Test yourself: Western Australia speed limits and key road rules

Answer each question, then read the explanation. Questions come in a random order each time.

Go deeper

• Learning to Drive in WA
• Moving to WA
• Country Driving in WA