Arizona speed limits and key traffic laws

By the end of this topic you can

• You can explain the reasonable and prudent speed rule.
• You can state the default limits for business and residential districts and school crossings.
• You can explain when you must stop for a school bus.
• You can describe what Arizona's move-over law asks you to do.
• You can explain why you must never drive around flood barricades.

What you need to know and understand

• Where no other limit is posted, 25 mph applies in business and residential districts.
• The school crossing limit is 15 mph between the portable school crossing signs, and fines are doubled where signs say so.
• Passing another vehicle in a school crossing zone is prohibited.
• Interstate limits are generally 65 mph and can be raised to 75 mph where posted.
• Driving more than 20 mph over the posted limit can be charged as excessive speed, a criminal offense.
• A first school bus violation carries a minimum civil penalty of $250.
• A move-over violation carries a $275 civil penalty for a first offense.
• Drivers who go around barricades into a flooded road can be billed up to $2,000 for their rescue.

Speed: signs, defaults and conditions

Posted limits are the maximum in good conditions. In heavy traffic, rain, dust or darkness, the reasonable and prudent rule means you must go slower. Where no limit is posted, Arizona law treats 25 mph as the limit in business and residential districts.

School crossing zones use portable signs placed in the road. Between those signs the limit is 15 mph, and you must not pass other vehicles.

Stopping for school buses

When a school bus has stopped with its stop signal out and red lights flashing, drivers in both directions must stop before reaching it. Stay stopped until the bus moves or turns off its signals. The only exception is a road with separate roadways, such as a divided highway, where you are on the other roadway. A center two-way turn lane does not create a separate roadway.

Move over and emergency vehicles

• Approaching any stationary vehicle showing flashing or warning lights on a road with two or more lanes in your direction: move out of the lane next to it if it is safe.
• If you cannot change lanes safely: slow down and pass with care.
• When an emergency vehicle approaches using lights and siren: pull to the right edge, clear of intersections, and stop until it passes.
• Following a responding emergency vehicle: the manual says keep at least 500 feet behind a fire vehicle and 300 feet behind a police vehicle.

Flooded roads and washes

Summer monsoon storms can turn dry washes into fast rivers within minutes. Never drive around barricades onto a flooded road. Besides the danger, Arizona law lets agencies charge you up to $2,000 for an emergency rescue.

Common mistakes

• Treating the posted limit as a target in poor conditions.
• Driving past a stopped school bus on a road with a center turn lane. That lane does not make it a divided road.
• Staying in the lane next to a stopped patrol car or tow truck when you could safely move over.
• Trying to cross a flooded dip because it looks shallow.

Test yourself: Arizona speed limits and key traffic laws

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

Go deeper

• Arizona 30-Hour Supervised Driving Log and Driver Ed Options
• Arizona Class G License Restrictions
• Arizona DUI and Extreme DUI Rules for New Drivers