Arizona's desert highways and urban corridors demand specific knowledge of state traffic laws to navigate safely and legally. This comprehensive guide breaks down the Arizona Revised Statutes (ARS) Title 28 into practical, actionable rules for everyday driving. Whether you're questioning double yellow line restrictions on Interstate 10, understanding right-turn-on-red rules in Phoenix metro areas, or navigating school bus stop requirements in Tucson neighborhoods, this page delivers clear answers with official statute references. Learn what Arizona law actually says about passing zones, U-turns, pedestrian crosswalks, speed limits, and desert driving hazards.
Arizona highways feature strict centerline rules—understand when you may legally cross double yellow lines.
Arizona double yellow line rules & no-passing zones (ARS 28-751)
Double yellow centerlines are Arizona's primary method for marking no-passing zones on two-lane highways and residential streets. Under ARS 28-751, drivers must not cross these lines to pass another vehicle traveling in the same direction. However, Arizona law recognizes specific exceptions where crossing double yellow lines is both legal and necessary for safe navigation. Understanding these exceptions prevents unnecessary citations and keeps traffic flowing efficiently around common roadway obstacles.
When crossing double yellow is legal in Arizona
Arizona permits drivers to cross double yellow lines in three specific situations: when making a left turn into a driveway, alley, or private road; when executing a legal U-turn at an intersection or designated opening; and when avoiding an obstruction blocking your lane. The key requirement is that the maneuver must be executed safely, with clear visibility of oncoming traffic and sufficient space to complete the movement without creating a hazard. These exceptions do not authorize passing slower vehicles in marked no-passing zones—that remains a citable violation under Arizona law.
Left turns across double yellow into driveways and alleys
When approaching your driveway or a business entrance across double yellow lines, signal early—at least 100 feet before the turn point. Check your rearview mirror for following traffic and scan oncoming lanes for approaching vehicles. Position your vehicle as close to the centerline as safely possible without crossing until you initiate the turn. Complete the turn at a speed that allows you to yield to any pedestrian or cyclist using the sidewalk or driveway apron. Never stop with your vehicle partially blocking the through lane while waiting for oncoming traffic to clear; if the gap is insufficient, proceed past the driveway and find a safer location to turn around using a center turn lane or legal U-turn opportunity.
Signal timing and gap selection for safe left turns
Arizona Department of Transportation (ADOT) recommends maintaining a sight distance of at least 500 feet when crossing opposing lanes. At highway speeds (55-65 mph), oncoming vehicles cover approximately 80-95 feet per second, meaning a vehicle that appears distant can reach your turn point in just 5-6 seconds. Factor in deceleration time, turn execution, and acceleration to clear the intersection—a complete left turn across double yellow lines typically requires 7-10 seconds of clear time. If you cannot confirm this gap exists, continue past the intended turn and locate a signalized intersection or marked turn lane.
Common citation scenarios: left turns without adequate gaps
Arizona Department of Public Safety (DPS) officers frequently cite drivers who force oncoming traffic to brake or swerve during left turns across double yellow lines. The standard is whether your turn caused another driver to alter speed or direction—if it did, you likely violated the requirement to yield right-of-way. Citations typically reference ARS 28-751 (improper lane use) or ARS 28-772 (failure to yield when turning left). Dashboard camera footage and witness statements often support these violations, making them difficult to contest without clear evidence of an emergency or road defect.
Avoiding obstructions: temporary hazards and road debris
Arizona law allows crossing double yellow lines to avoid an obstruction when remaining in your lane would be impossible or unsafe. Qualifying obstructions include disabled vehicles, fallen cargo, construction materials, large debris, animals, or emergency responders working in the roadway. The critical legal standard is "necessary and safe"—you may only cross as far left as needed to clear the hazard, and only when no oncoming traffic is present or approaching within your sight distance. Slow-moving vehicles, bicycles traveling lawfully in the roadway, and normal traffic congestion do not qualify as obstructions under Arizona statute.
What qualifies as an obstruction vs passing slow traffic
The distinction between a lawful obstruction and illegal passing lies in whether the road user ahead has a legal right to occupy the lane. A stalled vehicle blocking the through lane qualifies as an obstruction; a cyclist riding on the shoulder or in a designated bike lane does not. Farm equipment traveling below the speed limit but maintaining the right edge of the roadway does not constitute an obstruction, even if overtaking is inconvenient. Arizona courts consistently hold that driver convenience does not override no-passing zone restrictions—if the road ahead is marked with double yellow lines, wait for a passing zone with broken yellow markings or a dedicated passing lane.
Legal: crossing for left turns and obstructions. Illegal: passing vehicles in no-passing zones.
Right turn on red laws in Arizona (ARS 28-645)
Arizona permits right turns on red signals after a complete stop, unless prohibited by posted signage. This rule, codified in ARS 28-645, requires drivers to stop at the marked limit line, before entering the crosswalk, or at a point where they can see approaching traffic if no markings exist. After stopping completely, drivers must yield to all pedestrians, cyclists, and vehicles lawfully within the intersection or approaching close enough to constitute an immediate hazard. The right turn may be completed only when the driver can safely enter the intersection and merge into the rightmost lane without causing other road users to brake, swerve, or otherwise adjust their path.
Complete stop requirements at limit lines and crosswalks
A complete stop means wheels stop rotating, the vehicle remains stationary for at least one full second, and the front bumper stays behind the limit line or crosswalk edge. Rolling stops—where the vehicle slows to near zero but never fully halts—are among the most common traffic violations at Arizona intersections. Red light cameras, widely deployed in Phoenix, Scottsdale, Tempe, and Tucson, automatically capture vehicles that fail to stop or stop beyond the limit line. Stopping in the crosswalk is a separate violation under ARS 28-855, with fines typically ranging from $150 to $300 depending on jurisdiction, plus potential defensive driving school requirements.
"NO TURN ON RED" signs and time-based restrictions
When a sign reads "NO TURN ON RED," the prohibition applies at all times unless a time-restriction plaque appears below the main sign. Common time restrictions include "7-9 AM & 4-6 PM Weekdays" or "When Pedestrians Present." During unrestricted hours, the standard right-on-red rules apply; during restricted periods, you must wait for a green signal or green arrow before turning. Some Arizona cities use dynamic message signs that activate "No Turn" restrictions during school zone hours or special events—always check for illuminated messages or time plaques before proceeding on red.
Pedestrian right-of-way and leading pedestrian intervals (LPI)
Arizona intersections increasingly use leading pedestrian intervals, which give pedestrians a 3-7 second head start before vehicles receive a green signal. During an LPI phase, the pedestrian signal displays "WALK" while the traffic signal remains red. Drivers intending to turn right on red must yield completely during this phase—even though the traffic signal is red, pedestrians have exclusive right-of-way. Failure to yield to a pedestrian in a crosswalk carries enhanced penalties in Arizona, including potential points on your driving record and mandatory traffic survival school attendance.
Red light camera enforcement and citation appeal process
Arizona photo enforcement systems capture violations when a vehicle enters an intersection after the signal turns red, typically defined as any part of the vehicle crossing the limit line after the red indication begins. Citations are mailed to the registered owner with photographic evidence and a notice of violation. Registered owners may respond by identifying the actual driver, paying the fine, or requesting a court hearing. At hearing, successful defenses typically involve demonstrating the vehicle stopped before the limit line, proving the signal timing was defective, or showing emergency circumstances justified the movement. Simply ignoring photo enforcement citations can lead to default judgments and suspended license privileges.
Left turn on red in Arizona (one-way to one-way rule)
Arizona law permits left turns on red when turning from a one-way street onto another one-way street, provided the driver comes to a complete stop and yields to all traffic and pedestrians. This exception, less well-known than right-on-red, follows the same principles: stop behind the limit line, confirm both streets run one-way in the appropriate directions, check for prohibitive signage, and only proceed when no conflict exists with pedestrians, cyclists, or vehicles lawfully in the intersection. Downtown Phoenix, Tucson, and Flagstaff have several one-way street grids where this rule applies, though posted signs at some intersections specifically prohibit the movement during peak hours or at locations with poor sight lines.
Confirming one-way street status and checking for prohibition signs
Verify one-way status by observing pavement arrows, "ONE WAY" signs facing your direction, and the absence of opposing traffic lane markings. Both the street you're leaving and the street you're entering must be signed one-way; a left turn from one-way to two-way does not qualify. Look for "NO TURN ON RED" or "NO LEFT TURN ON RED" signs mounted on signal poles or mast arms. In heavy pedestrian areas, Arizona cities sometimes post prohibition signs without time restrictions to protect foot traffic—these apply 24/7.
Right on red: stop, yield, proceed when clear. Left on red: only one-way to one-way after complete stop.
Arizona U-turn laws and restrictions (ARS 28-751, 28-754)
U-turns are legal in Arizona when executed safely and not prohibited by posted signs or pavement markings. State law imposes several location-based restrictions: U-turns are prohibited where visibility is obstructed within 500 feet in either direction (such as curves, hills, or bridge approaches), in business districts except at intersections controlled by traffic signals, and at any location where a sign specifically bans the maneuver. When legal, U-turns may be performed across double yellow lines at intersections, though drivers must yield to all approaching traffic, pedestrians, and cyclists throughout the entire maneuver. Improper U-turns frequently result in citations under ARS 28-754 (prohibited U-turns) or ARS 28-772 (failure to yield during turns).
Legal U-turn locations: intersections with traffic signals
The safest and most clearly legal U-turn opportunities occur at signalized intersections in non-business districts. When the traffic signal is green for your direction of travel, you may turn left and execute a U-turn, provided no sign prohibits U-turns and you can complete the maneuver within the intersection without impeding traffic. Use the leftmost lane when approaching, signal left continuously, yield to oncoming traffic, and complete the turn into the correct lane for your new direction of travel. Wide intersections with generous turning radii make U-turns easier; compact intersections may require multi-point turns or alternative routes.
Business district U-turn restrictions and definitions
Arizona defines business districts as areas with buildings used for business or industrial purposes occupying at least 300 feet of frontage on one side or 300 feet collectively on both sides of the highway. Within these districts, U-turns are only permitted at intersections controlled by traffic signals—mid-block U-turns remain prohibited regardless of traffic conditions. Determining whether a specific location qualifies as a business district can be challenging; when uncertain, treat any commercial corridor with continuous building frontage as a business district and restrict U-turns to signalized intersections.
Arizona prohibits U-turns where the driver cannot see approaching traffic within 500 feet in both directions. This restriction applies to curved roads, hill crests, bridge approaches, tunnels, and any location where buildings, vegetation, or terrain block long-range visibility. At highway speeds (55-65 mph), 500 feet provides only 5-7 seconds of reaction time for approaching drivers—barely sufficient to recognize a U-turning vehicle and respond safely. Always choose U-turn locations with maximum sight distance, even where the statutory minimum is met. Elevated interchanges, open desert straightaways, and flat grid-pattern streets offer the safest conditions for U-turn execution.
Residential area U-turns and painted median restrictions
Residential streets generally allow U-turns unless specifically posted otherwise, provided visibility and safety requirements are met. However, many Arizona cities have installed painted median barriers—two sets of double yellow lines with space between—along major residential collectors and arterials. These painted medians function like physical barriers; crossing them for U-turns is prohibited except at designated openings marked by breaks in the yellow lines. Look for "authorized left turn only" zones where the painted median opens to accommodate turns into driveways, side streets, or commercial parking lots.
School bus stop laws in Arizona (ARS 28-857)
Arizona requires all motorists to stop for school buses displaying flashing red lights and an extended stop arm, with limited exceptions for divided highways. On undivided roadways—including two-lane roads, multilane streets without physical medians, and roads separated only by painted lines—traffic traveling in both directions must stop and remain stopped until the red lights cease flashing and the stop arm is retracted. Violations of ARS 28-857 carry substantial penalties: fines ranging from $250 to $750, potential suspension of driving privileges, and mandatory traffic safety school attendance. Repeat violations within 36 months trigger enhanced penalties including possible jail time.
Both-direction stopping requirements on undivided roads
When approaching a stopped school bus on any undivided roadway, drivers must stop at least 15 feet from the bus and remain stopped until the bus driver deactivates the red lights and retracts the stop arm. This requirement applies even on wide multilane roads where you might assume children will not cross your lane— Arizona law presumes children may cross unexpectedly from either side of the bus. Drivers should reduce speed when school buses are visible ahead, watch for amber warning lights that precede the red stop lights, and prepare to stop with adequate space to avoid rear-end collisions with following traffic.
Divided highway exception: physical barriers and unpaved medians
Arizona provides an exception for traffic traveling on divided highways separated by physical barriers (concrete walls, metal guardrails) or unpaved medians at least five feet wide. In these situations, only traffic traveling in the same direction as the school bus must stop; opposing traffic may proceed with caution at reduced speed. Paved medians, painted median barriers (two sets of double yellow lines), and turn lanes do not qualify as dividing barriers—if the median is paved or consists only of painted lines, all traffic must stop regardless of direction. When uncertain whether a median qualifies for the exception, err on the side of caution and stop.
Undivided roads: all traffic stops. Divided highways with physical median: opposing traffic may proceed cautiously.
Arizona speed limits and basic speed law (ARS 28-701)
Arizona's basic speed law, ARS 28-701, requires all drivers to operate at speeds "reasonable and prudent under the circumstances then existing." This means posted speed limits are not absolute safe speeds—drivers must adjust for weather conditions, traffic density, visibility, road surface quality, and other factors. You can be cited for traveling at or below the posted limit if conditions make that speed unsafe. Conversely, exceeding the posted limit is illegal regardless of road conditions unless expressly authorized by temporary signs (such as in construction zones) or when passing to avoid hazards.
Absolute speed limits: posted limits you must not exceed
Arizona establishes absolute maximum speed limits on various roadway types: 15 mph in school zones when children are present, 25 mph in residential districts, 65 mph on most rural highways, and 75 mph on designated interstate segments. Exceeding these limits by any amount constitutes a violation, though enforcement tolerance varies by jurisdiction and circumstances. Speed enforcement is particularly strict in school zones, construction zones, and areas with high pedestrian activity. Photo radar systems, common on Phoenix-area freeways and arterials, automatically ticket vehicles exceeding posted limits by 11 mph or more.
Minimum speed requirements on Arizona highways
Arizona law prohibits driving so slowly as to impede the normal flow of traffic, except when reduced speed is necessary for safe operation or legal compliance. On limited-access highways, minimum speed limits are sometimes posted—typically 40 or 45 mph on interstate segments with 65-75 mph maximum limits. Drivers unable to maintain minimum speeds due to vehicle limitations should use slower-traffic lanes and activate hazard flashers if falling significantly below prevailing speeds. Excessively slow driving can result in citations for impeding traffic under ARS 28-704.
Desert driving considerations: dust storms and visibility
Arizona's desert climate creates unique speed-related hazards, particularly during monsoon season (July-September) when severe dust storms ("haboobs") reduce visibility to near-zero within seconds. When encountering dust storms, ADOT advises: "Pull aside, stay alive." Never stop in travel lanes; exit the roadway completely if visibility drops below safe levels. If exiting is impossible, reduce speed gradually, activate hazard lights, and maintain lane position until conditions improve. High-wind warnings are common in exposed desert corridors; reduce speed and increase following distance when alerts are active.
Work zone speed limits and enhanced enforcement
Arizona doubles fines for speeding violations in active work zones where workers are present or lane closures are in effect. Temporary speed limit signs with orange backgrounds indicate work zone restrictions, often reducing highway speeds to 55 mph or lower. Flagger instructions override posted limits and traffic signals— when a flagger signals you to stop, proceed, or slow, follow their direction immediately. Construction zone speeding citations carry enhanced fines ($500-$1000 or more), points on your driving record, and potential license suspension for extreme violations (20+ mph over the reduced limit).
Pedestrian crosswalk laws in Arizona (ARS 28-792, 28-793)
Arizona law grants pedestrians right-of-way in crosswalks, both marked and unmarked, at intersections. Drivers must yield when pedestrians are within the crosswalk or approaching closely enough that continuing would create a hazard. This requirement applies even to unmarked crosswalks—the legal crosswalk at an intersection extends across the roadway within the imaginary extension of sidewalks or property lines, whether or not painted lines exist. Failure to yield carries fines of $300-$500 plus two points on your driving record. When pedestrians cross outside marked crosswalks mid-block (jaywalking), drivers should still exercise caution, but pedestrians must yield right-of-way to vehicles in this scenario.
Marked versus unmarked crosswalks at intersections
Marked crosswalks feature painted lines (parallel lines, ladder patterns, or zebra stripes) and sometimes advance warning signs or enhanced lighting. Unmarked crosswalks exist at virtually all public intersections where sidewalks meet, even without pavement markings. Drivers turning through intersections must scan for pedestrians in both marked and unmarked crosswalks before completing turns. Downtown areas, shopping districts, and residential neighborhoods with grid-pattern streets often have numerous unmarked crosswalks where pedestrian activity is high and driver awareness is critical.
Mid-block crossing rules and pedestrian jaywalking
Outside of marked or unmarked crosswalks, pedestrians crossing roadways must yield to all vehicles. However, Arizona drivers remain responsible for exercising due care to avoid colliding with pedestrians, regardless of who has legal right-of-way. When you observe pedestrians crossing mid-block illegally, reduce speed, flash headlights if it's safe to draw attention, and provide ample clearance. Never pass other stopped vehicles at crosswalks without confirming no pedestrians are present—stopped traffic may be yielding to a pedestrian you cannot yet see.
This guide provides general information based on Arizona Revised Statutes and is not legal advice. Always consult official statute text, posted signs, and traffic control devices for authoritative guidance. Traffic laws are subject to change; verify current requirements with ADOT or legal counsel for specific situations.
