Speed limits aren’t just numbers on signs — they shape how we drive, how crashes happen, and how serious the consequences can be. In Arizona, where wide highways meet crowded city streets, the rules about speed are more complex than most people realize. If you’ve ever been in a crash or worried about what could happen, understanding how speed limits really work might matter more than you think.
What Is the Speed Limit in Arizona?
In Arizona, speed laws are guided by Arizona Revised Statutes (ARS) § 28-701, which says drivers must travel at a “reasonable and prudent” speed based on actual road, weather, and traffic conditions. Even if a posted sign allows a certain speed, you’re still required to slow down if the situation calls for it.
The default statewide maximum is 65 mph, unless otherwise posted. That limit applies to most highways, city roads, and surface streets outside of special zones.
Arizona Speed Limit Laws and Local Regulations
Arizona’s speed limit laws are guided by state statutes, but local cities and towns can set their own limits based on traffic needs, street design, and safety concerns. While the statewide rules under ARS § 28-701 provide the foundation — like 25 mph in residential areas and 65 mph on most highways — municipalities can lower or raise limits if engineering studies support the change.
For example, cities like Scottsdale, Tempe, and Tucson may reduce limits near parks, schools, or high-pedestrian zones, even below the state default. In some neighborhoods, you might see posted limits as low as 15 or 20 mph, and those are fully enforceable. City governments often use speed cushions, radar signs, and increased patrols in these zones. So even if you’re familiar with the state laws, always watch for posted signs — local rules may be stricter, and failing to follow them can put you at fault in a crash or facing a higher fine.
What’s the Highest Speed Limit in Arizona?
The highest legal speed in the state is 75 mph, and it applies only on rural interstates — typically long, open stretches of I-8, I-10, or I-40 far from city congestion. These highways are designed for higher-speed travel with fewer access points and lower crash risks.
Arizona Highway and Freeway Speed Limits
Urban Interstates and Freeways in City Limits
Inside cities — like Phoenix, Tucson, and Flagstaff — urban interstates such as I-17, I-10, Loop 101, or Loop 202 usually have a posted speed limit of 65 mph, which also applies to trucks unless signage says otherwise.
Other State Highways
Other state highways and limited-access roads not considered freeways also generally post 65 mph, but conditions, congestion, and development along the route may bring that down.
Is It Ever Legal to Exceed the Speed Limit on a Highway?
No. Arizona law does not allow any exceptions for exceeding posted speed limits — not even to pass another vehicle. Exceeding the limit at any time is considered illegal, regardless of traffic flow.
Residential, Business, and School Zone Speed Limits in Arizona
What’s the Speed Limit in Residential Areas?
The speed limit in residential neighborhoods is 25 mph, whether or not a sign is posted. That includes areas with homes, driveways, kids playing, and local foot traffic.
Maximum Speed Limit for Business Districts
In business zones, the default limit is also 25 mph, designed to protect pedestrians, local shoppers, and high-turnover parking areas.
What’s the Speed Limit in a School Zone?
When children are present and signs or flashing lights are active, the limit in school zones drops to 15 mph. These are strictly enforced, especially during pick-up and drop-off hours. Even small violations here can lead to heavy fines.
Can You Go 5 Miles Over the Speed Limit in Arizona?
No — while many drivers believe there’s a 5 mph cushion, there’s no legal allowance for going over the limit. Even driving 1 mph over is technically a violation under ARS § 28-701. Some officers may issue warnings, but you’re still breaking the law, and photo radar systems don’t give that leeway.
How Much Can You Go Over the Speed Limit in Arizona?
Zero miles. Arizona has no built-in forgiveness for “a few miles over.” You can be ticketed — or even criminally charged — for excessive speeding depending on how far over the limit you’re going. Once you pass the posted number, you’re at risk.
How Many Miles Under the Speed Limit Can You Go?
Driving too far below the speed limit can also get you cited, especially if you’re obstructing traffic. ARS § 28-701 says you must drive at a speed that’s not just safe, but also reasonable based on conditions — which includes keeping up with traffic flow when appropriate. If you’re going 15-20 mph under without a good reason (bad weather, mechanical trouble), it could be seen as a hazard.
Where Else Are Speed Limits Regulated Differently in Arizona?
Not all speed limits in Arizona fit neatly into statewide defaults. In certain areas, unique road conditions or local safety concerns lead to special speed regulations that drivers are expected to follow — and violations here can carry steeper penalties.
- Construction zones: Temporary limits are posted and strictly enforced, often with doubled fines.
- Photo radar enforcement areas: Cities like Scottsdale, Paradise Valley, and others use automated systems to issue tickets, even for minor violations.
- Mountain roads and rural curves: Speed signs may drop dramatically due to tight turns, inclines, or visibility limits. These overrides are still legally binding.
- Alleys or private drives: May have posted limits even lower than 25 mph depending on municipal rules.
Speed limits in Arizona do more than guide traffic — they shape how drivers move, how safely they interact, and what legal consequences follow a crash. Whether you’re cruising through the desert or driving your kids to school, knowing where the law draws the line helps keep you and everyone else on the road safer.
What If There’s No Speed Limit Sign Posted?
If there’s no speed limit sign posted, that doesn’t mean you’re free to drive as fast as you want. In Arizona, default speed limits still apply — even without a sign. That means 25 mph in residential or business districts, 65 mph on most highways, and 15 mph near schools when children are present. If you’re in an unfamiliar area and can’t spot a posted limit, assume the default applies. And if the road conditions call for it — sharp curves, poor visibility, heavy traffic — you’re legally required to slow down, even if you’re well under the technical limit.
Penalties for Speeding in Arizona
In most cases, speeding in Arizona is treated as a civil traffic violation — but that doesn’t mean it’s harmless. If you’re caught driving over the posted speed limit but not beyond criminal thresholds, you can expect a fine between $150 and $250, depending on how far over the limit you were and whether you were in a school zone, construction zone, or residential area (where fines often increase). You’ll also get 3 points added to your driving record. If you accumulate too many points over time, the Arizona MVD may require you to attend Traffic Survival School, and in some cases, you could face a license suspension. On top of that, even one minor ticket can cause your insurance rates to spike, especially if you’ve had previous violations.
When Speeding Becomes a Crime: Criminal Speeding in Arizona
Speeding crosses into criminal territory when you hit certain thresholds outlined in ARS § 28-701.02. You can be charged with criminal speeding — a class 3 misdemeanor — if you’re caught doing over 85 mph anywhere, driving more than 20 mph over the posted limit, exceeding 45 mph in an unposted residential or business area, or going over 35 mph in a school zone. These aren’t just tickets — they’re criminal charges. Penalties may include up to 30 days in jail, a fine of up to $500 plus court costs, 3 points on your license, and possible license suspension. You’ll also be required to appear in court, and a conviction could leave you with a permanent criminal record, affecting your insurance, job opportunities, and future driving privileges.
How Speeding Impacts a Car Accident Case in Arizona
When speeding leads to a crash in Arizona, the consequences go from serious to life-changing in seconds. Speed is one of the top contributing factors in fatal car accidents across the state. In 2022 alone, nearly one-third of all traffic deaths in Arizona involved speeding, according to crash data from ADOT. The faster a vehicle moves, the harder the impact — and the less time there is to react, avoid obstacles, or brake safely. In personal injury cases, speeding often shifts the legal outcome, too. If a driver was going over the limit — even slightly — and caused a crash, they’re far more likely to be found at fault. That means higher liability, a tougher legal defense, and reduced chances of recovering damages if you were the one speeding. Insurance companies use speed as a key factor when determining who’s responsible, and in court, it’s one of the first things attorneys investigate. Whether you’re a victim or being blamed for a collision, speed doesn’t just raise the danger — it can define the entire case.
We Know How Speed Affects Your Case — And We Know How to Win It
At Esquire Law, we’ve seen firsthand how speeding can change everything — from the severity of a crash to the outcome of a legal claim. Whether you were injured by a reckless driver going too fast or you’re being unfairly blamed because of speed, these cases require careful investigation, strong evidence, and a legal team that knows how Arizona’s traffic laws really work. Our Phoenix car accident attorneys know what it takes to prove fault, challenge assumptions, and fight for the compensation you deserve — even when the insurance companies push back. If speed played a role in your accident, we’re ready to step in and build a case that puts your recovery and your rights first.