Left turn arrow signals come in four colors, and each one tells you something specific about whether you can turn and who has the right of way. A steady green arrow gives you a protected turn with oncoming traffic stopped. A steady yellow arrow warns that protection is ending. A flashing yellow arrow lets you turn only after yielding to oncoming vehicles and pedestrians. A steady red arrow prohibits the turn entirely. Knowing which rule applies to which color keeps you out of both crashes and traffic court.
Green Left Turn Arrow
A green left turn arrow means oncoming traffic has a red light and the signal system has cleared your path. You don’t need to yield to vehicles traveling in the opposite direction. The Manual on Uniform Traffic Control Devices says a green arrow permits you to “cautiously enter the intersection only to make the movement indicated by such arrow.”1Federal Highway Administration. Manual on Uniform Traffic Control Devices 11th Edition
Protected doesn’t mean unconditional. You still have to yield to pedestrians finishing their crossing and to any vehicles already lawfully inside the intersection when your arrow turned green.1Federal Highway Administration. Manual on Uniform Traffic Control Devices 11th Edition A driver who entered on the previous phase has every right to clear, and hitting them will land you with a failure-to-yield citation regardless of what color your arrow is. Scan the crosswalk and the intersection box before you commit.
Steady Yellow Left Turn Arrow
A steady yellow arrow warns that your protected green phase is about to end. If you haven’t yet entered the intersection, prepare to stop. If you’re already partway through your turn, finish clearing the intersection before conflicting traffic gets a green signal.
Entering the intersection after the signal turns red is a red-light violation in every state. Convictions commonly add points to your driving record and push your insurance premiums up. Yellow intervals are timed based on the approach speed and the distance a vehicle needs to either stop or clear the intersection,2Federal Highway Administration. Traffic Signal Timing Manual Chapter 5 so if you’re close enough that stopping would require slamming the brakes, finish the movement; if you have room to stop safely, stop.
Flashing Yellow Left Turn Arrow
A flashing yellow arrow means you may turn left, but you no longer have protection. Oncoming traffic has a green light. You must yield to every vehicle approaching from the opposite direction and to any pedestrians in the crosswalk, then proceed only when you find a safe gap.1Federal Highway Administration. Manual on Uniform Traffic Control Devices 11th Edition
This display replaced the old circular green ball that many intersections used for permissive left turns. Drivers sometimes misread the circular green as a protected phase, especially during a hazard engineers call the “yellow trap”: your side gets a yellow while oncoming traffic still has a green, and a turning driver assumes oncoming cars are also stopping. The flashing yellow arrow eliminates that confusion because its meaning is unambiguous: oncoming traffic is still coming.3Federal Highway Administration. Traffic Signal Timing Manual Chapter 4
The safety data supported the switch. An FHWA evaluation found that intersections converted to flashing yellow arrow displays saw a 15 to 50 percent reduction in left-turn crashes, depending on the previous signal configuration.4Federal Highway Administration. Safety Evaluation of Flashing Yellow Arrow at Signalized Intersections
Misjudging the speed of an approaching vehicle is one of the most common ways drivers get hit during a flashing yellow. If a car coming toward you is close enough that it would need to brake for your turn, the gap isn’t safe. Law enforcement regularly writes failure-to-yield citations in these situations, with fines and sometimes mandatory traffic safety courses depending on your jurisdiction.
Steady Red Left Turn Arrow
A steady red arrow is a flat prohibition. You cannot turn in the direction the arrow points. Stop at the limit line, or if there’s no line, before the crosswalk. If there’s no crosswalk either, stop before entering the intersection, and stay put until the signal changes.1Federal Highway Administration. Manual on Uniform Traffic Control Devices 11th Edition
This is where drivers get tripped up. At a circular red light, most states allow you to turn right (or left from one one-way street onto another) after a complete stop. A red arrow is different. Under the MUTCD, you can only turn on a red arrow if a separate sign at that intersection specifically authorizes it.1Federal Highway Administration. Manual on Uniform Traffic Control Devices 11th Edition Without that sign, the turn is illegal. Running a red arrow is treated as a serious moving violation in every state, and the fines after court surcharges can be substantial.
Left on Red From a One-Way Street
A majority of states allow a left turn on a circular red signal after a complete stop when you’re turning from a one-way street onto another one-way street. About eight states and Washington, D.C. prohibit left turns on red entirely. Even where the general one-way-to-one-way rule applies, a red arrow still blocks the turn unless a posted sign says otherwise. If you drive in an unfamiliar state, confirm the local rule before assuming a left on red is permitted.
U-Turns at Left Turn Arrows
A green left turn arrow generally permits a U-turn at that intersection as long as no sign prohibits it. The MUTCD groups U-turn movements with left turns when describing what a green arrow allows, so the same protected phase that lets you turn left also lets you reverse direction.1Federal Highway Administration. Manual on Uniform Traffic Control Devices 11th Edition Some jurisdictions restrict U-turns at specific intersections or near land uses such as fire stations or school zones, and a “No U-Turn” sign overrides the green arrow.
During a flashing yellow, a U-turn is riskier and sometimes prohibited. Even where it’s legal, completing a U-turn during a permissive phase demands a larger gap than a standard left turn because of the wider arc and slower speed involved.
When the Signal Won’t Detect Your Vehicle
Many left turn lanes use inductive loop detectors embedded in the pavement to know a vehicle is waiting. The loops sense changes in a magnetic field when metal passes over them. Cars and trucks trigger them reliably. Motorcycles and bicycles often don’t. A motorcycle can cause an inductance change as small as 0.012 percent on a standard loop, which may not be enough to register.5Eberle Design Inc. Inductive Loop Detector Basics You end up sitting at a red left turn arrow that never changes.
Over 20 states have addressed this with “dead red” laws that let motorcyclists, and sometimes cyclists, treat an unresponsive red signal like a stop sign. The rules vary. Some states require waiting through one or two full signal cycles, others set a specific time such as 90 or 120 seconds. In states without a dead red law, your options are more limited: turning right and looping back, or waving a car behind you to pull forward over the sensor, are common workarounds.
If you ride a motorcycle, positioning your wheels directly over the visible saw-cut lines in the pavement, where the loop wire is buried, gives you the best chance of triggering the sensor. The magnetic field is strongest right at the wire, not in the center of the loop.
Pedestrians and Cyclists
Every type of left turn arrow requires you to yield to pedestrians lawfully in the crosswalk. That duty applies during a protected green arrow, during a flashing yellow, and even after your light changes if someone is still finishing their crossing. The MUTCD spells it out for every signal indication: turning traffic yields to pedestrians in the associated crosswalk.1Federal Highway Administration. Manual on Uniform Traffic Control Devices 11th Edition
The conflict is sharpest during the flashing yellow phase, because pedestrians crossing the street you’re turning onto often have a walk signal at the same time. Some intersections now use a leading pedestrian interval, activating the walk signal several seconds before any vehicle gets a green or flashing yellow so pedestrians are already visible in the crosswalk when drivers start turning.6Federal Highway Administration. Leading Pedestrian Interval
Cyclists get the same priority. A bicycle traveling straight through the intersection has the right of way over a left-turning vehicle during both protected and permissive phases. Bikes are harder to see than cars and easier to misjudge for speed. Striking a pedestrian or cyclist carries consequences well beyond a traffic ticket, including potential criminal charges when injuries are serious and civil liability that can exceed insurance coverage.