When to Use Your Turn Signal: What the Law Expects and What Keeps You Safe

Use your turn signal every time you change direction or lateral position: before turns, lane changes, merges, entering or exiting roundabouts, pulling away from or toward the curb, entering/exiting parking spaces or driveways, overtaking, and exiting the roadway—activating it early (typically at least 100 feet or about 3 seconds in city driving, and earlier at higher speeds) and canceling it once the maneuver is complete. While specific rules vary by region, the principle is universal: signal early, signal consistently, and signal even when you think no one is watching, because other road users may depend on it.

Why Signaling Matters

Turn signals are your vehicle’s simplest communication tool. They set expectations, reduce surprises, and help prevent sideswipes, rear-end crashes, and conflicts with pedestrians and cyclists. In most jurisdictions, signaling is not just courtesy—it’s a legal requirement enforceable by fines, points, and, in the event of a crash, potential liability.

Situations That Require Your Turn Signal

The following are the core traffic situations where drivers are expected—or legally required—to indicate their intent. Signaling should be continuous from the moment you begin to communicate your intention until the maneuver is complete.

• Turning left or right at intersections, including turn-only lanes.
• Changing lanes on any road, including multi-lane roundabouts and expressways.
• Merging onto or exiting highways, ramps, and slip roads.
• Entering and, especially, exiting roundabouts.
• Pulling away from the curb, shoulder, or a parked position.
• Pulling over to the side of the road, entering/exiting driveways, alleys, or parking spaces.
• Passing/overtaking and returning to lane on two-lane roads.
• Re-entering traffic after a stop or yield.

If in doubt, signal. Many codes say to signal “when other traffic may be affected,” but you can’t reliably know who’s watching. The safest and most enforceable habit is to signal for every movement.

How Early to Signal

Timing rules vary by country and state, but the goal is the same: give others enough time to react. Use these widely accepted benchmarks unless your local law specifies longer distances.

• Urban/low-speed roads: signal for at least the last 100 feet (about 30 meters) before a turn or lane change, or for at least 3 seconds.
• High-speed roads: begin signaling earlier—many jurisdictions require or recommend 200 feet (60 meters) or more, and some specify up to 300 feet at higher speeds.
• Multiple lane changes: signal, check, and move one lane at a time, maintaining the signal as long as your intention continues.
• Turn lanes and red lights: keep your signal on while waiting to turn; do not rely on the lane’s markings alone.
• After the maneuver: cancel immediately to avoid misleading others.

When traffic is heavy, visibility is poor, or speeds are high, extend your signaling time. The higher the speed, the earlier other road users need the warning.

Roundabout Signaling by Region

Roundabouts have their own signaling etiquette, which differs by country. The aim is to show whether you’re exiting immediately, staying in the circle, or leaving at a later exit.

• United States/Canada: signal right as you approach your exit; do not signal left on entry. Keep right-turn signal on through the exit.
• United Kingdom/Ireland: per the Highway Code—signal left for the first exit; signal right if taking an exit past 12 o’clock (or otherwise “later”), then switch to left after passing the exit before yours to show you’re leaving.
• Australia/New Zealand: similar to the UK—signal left for the first exit, right for later exits, and left as you pass the exit before the one you intend to take; always signal left when exiting.
• Continental Europe: practices vary; many countries emphasize signaling on exit rather than on entry. Check the national code for specifics.

If you’re driving abroad, adopt the local roundabout signaling norms—police and other drivers will expect them, and they reduce confusion inside the circle.

Common Signaling Mistakes to Avoid

These frequent errors undercut the purpose of signaling and create unnecessary risk for you and others.

• Signaling too late—or not at all—especially during lane changes.
• Leaving the signal on after completing the maneuver, misleading others.
• Starting to move first and signaling as an afterthought.
• Using hazard lights to substitute for a turn signal or to change lanes.
• Relying solely on blind-spot monitors instead of signaling and checking mirrors/over-shoulder.
• Assuming a turn-only lane removes the need to signal—it doesn’t in many places.

Good signaling is proactive. Indicate, verify it’s safe, then move—never the other way around.

Special Cases: Cyclists, Motorcyclists, and Heavy Vehicles

Different vehicles face different signaling challenges. Here’s what to keep in mind if you ride or drive something other than a typical passenger car.

• Cyclists: use hand signals—left arm straight out for left; left arm bent up or right arm straight out for right; left arm down to indicate slowing/stopping. Signal early and maintain control.
• Motorcyclists: use the bike’s indicators and cancel them manually; supplement with lane positioning to make intent obvious.
• Trucks/buses: signal earlier due to longer stopping distances and larger blind spots; avoid “surprise” lane changes.
• Towing/long combinations: ensure trailer lights work and mirror the tow vehicle’s signaling.

Visibility and predictability are critical for vulnerable road users and heavy vehicles alike. Earlier, longer signals buy others time to react safely.

Weather, Visibility, and Driver-Assistance Systems

Conditions and technology can affect how your signals are perceived—and your legal responsibility doesn’t change.

• Rain, snow, fog, glare: signal earlier and keep it on longer; clean lens covers and ensure bulbs/LEDs are functional.
• Night driving: signals are more visible, but closing speeds can be deceptive—give extra time.
• Lane-change assist and “3-blink” features: verify that the auto-blink duration is long enough for the maneuver; add manual signaling if needed.
• Partial automation: even with adaptive cruise or lane centering, you must signal as required by law and best practice.

Technology helps, but it doesn’t replace your legal duty to communicate clearly and early with other road users.

Legal Notes and Penalties

Across North America, Europe, and beyond, signaling rules are codified and enforced. While exact wording varies, enforcement trends are consistent.

• Failure to signal is often a primary offense and can be grounds for a traffic stop.
• Tickets, points, and fines are common, and lack of signaling may be cited in crash reports and insurance determinations.
• Many jurisdictions require continuous signaling for a minimum distance/time before the maneuver; some specify longer distances on high-speed roads.

Check your local highway code for precise distances and definitions. Regardless, the safest and most defensible practice is to signal early and consistently.

A Quick, Reliable Signaling Checklist

Use this six-step sequence to keep your signaling clean, legal, and predictable in everyday traffic.

1. Decide on your maneuver and confirm it’s legal where you are.
2. Check mirrors and ahead for gaps and hazards.
3. Signal early—keep it on continuously.
4. Check blind spot(s); yield as required.
5. Execute the maneuver smoothly and decisively.
6. Cancel the signal as soon as you’re established in the new path.

Practiced consistently, this sequence becomes second nature—and significantly reduces your risk profile on the road.

Summary

Turn signals are essential, simple, and legally required: use them for every turn, lane change, merge, roundabout exit, pull-out, and pull-over; start early (about 100 feet/3 seconds in town, more at speed), keep them on through the maneuver, and cancel promptly. Regional rules differ—especially at roundabouts—but the universal standard is to signal proactively so others have time to respond. When in doubt, indicate.

How far in advance do you activate your turn signal?

Some states, such as California and Idaho, require drivers to signal five seconds before switching lanes to give anyone in traffic around you time to react. Of course, when you’re driving a car, you’re most likely to use the electric turn signals to communicate with others on the road.

What is a good rule for using turn signals?

The general rule is: Turn on your blinker about 100 feet before a turn. Signal at least three to five seconds before changing lanes.

What is the basic rule for using turn signals?

The basic rule for using turn signals is to signal your intention to turn, change lanes, or pull away from a curb at least 100 feet before making the maneuver, but not so early that other drivers might not know if you are going to turn. A signal should always be used, even if you don’t see any other vehicles around, to communicate your intentions and ensure safety.
 
When to use your turn signal

• Before any turn: Signal at least 100 feet before turning. 
• Before every lane change: Use your signal for at least three to five seconds before changing lanes. 
• Before pulling away from the curb: Signal to alert other drivers that you are moving into the lane. 
• When exiting a roundabout: Signal your intention to exit the roundabout. 

How to use your turn signal

• Check your surroundings: Before signaling, make sure it’s safe to change lanes or turn by checking traffic ahead, behind, and to your sides. 
• Use your turn signal lights: Use the vehicle’s signal lights, especially at night or in poor visibility conditions. 
• Use hand-and-arm signals when necessary: If your signal lights aren’t functioning, or in bright sunlight, you can use hand signals. 

Safety tips

• Signal early: Opens in new tabGive other drivers enough notice. 
• Be cautious of motorcycles: Opens in new tabDrivers often fail to see motorcycles, so be extra alert, especially when making turns. 
• Don’t rely on other drivers’ signals: Opens in new tabDrivers may signal incorrectly or change their minds, so never solely rely on another driver’s turn signal. 
• Keep your wheels straight: Opens in new tabWhen waiting to turn, keep your wheels straight to avoid being pushed into traffic if hit from behind. 

How soon should I turn my blinker on?

You should turn on your blinker at least 100 feet before making a turn or changing lanes in town to give other drivers and pedestrians enough time to react. On a freeway, you should signal at least five seconds before a lane change or about 900 feet before an exit. 
For Turns and Lane Changes in Town

• 100 feet rule: Opens in new tabSignal at least 100 feet before you intend to turn. This is a legal requirement in many states, including California. 
• Why 100 feet? Opens in new tabThis distance gives other drivers and pedestrians sufficient notice of your intentions, allowing them time to adjust their speed or position. 
• Don’t signal too early: Opens in new tabDon’t signal too far in advance, such as several blocks away, as it could confuse other drivers into thinking you’re turning at the wrong location. 

This video explains the importance of signaling 100 feet before a turn: 59sZutobi Drivers EdYouTube · Jan 27, 2022
For Freeways

• Lane Changes: Signal at least five seconds before a lane change. 
• Exits: Signal approximately 900 feet before you plan to exit. 

General Guidelines

• Consistency: Signal every time you intend to turn or change lanes, even if you don’t see other vehicles around. 
• “I intend to” not “I am”: Remember that your signal communicates your intention to turn or change lanes, not the action itself. 
• Turn it off: Remember to turn off your blinker once you no longer need it. 

You can watch this video to learn how to use turn signals correctly: 57sZutobi Drivers EdYouTube · Nov 9, 2022