How many seconds in advance should you signal before changing lanes while driving?

[BrandonDella]

Generally, you should turn on the turn signal about 10-20 seconds in advance before changing lanes. Here is some relevant information: 1. Lane changing: Lane changing refers to the driving operation where a vehicle moves from one lane to another while driving, such as when overtaking, avoiding obstacles, or turning at an intersection. 2. Do not decelerate after changing lanes: After changing lanes, do not decelerate; continue to accelerate momentarily while observing the speed of the vehicle in front and the distance between your vehicle and the one ahead. If your speed exceeds that of the vehicle in front, gradually release the accelerator pedal until your speed matches that of the vehicle ahead, maintaining an appropriate following distance.

[OWillow]

After years of driving, I've learned that lane changes should never be rushed. Experts recommend signaling at least 3-5 seconds in advance, and I find 4-5 seconds even safer. After signaling, don't immediately switch lanes—check your mirrors and blind spots first, ensuring no vehicles are approaching before gradually moving over. At higher speeds, you'll need to extend this timing, especially on highways where reaction times are shorter and mistakes can be catastrophic. I still remember one incident near a highway exit when I lazily signaled just 2 seconds ahead—the car behind honked aggressively and nearly rear-ended me, which was terrifying. Since then, I remind myself daily that safety comes first. Developing this habit isn't just lifesaving; it also makes driving smoother overall. Always monitor distances carefully during routine driving to prevent lane changes from becoming hazards—details make all the difference.

[GiannaLee]

When learning to drive, my instructor always nagged about changing lanes smoothly and emphasized signaling at least three seconds in advance. At first, I was impatient and would turn after just one or two seconds, until one time when a car scraped my side mirror—nearly causing an accident. Later, I learned my lesson: signal for three seconds, then check the surrounding traffic, especially during city rush hours when cars are numerous and slow-moving. Even then, it’s crucial to give trailing vehicles buffer time. Safety is built through habit—never rush a lane change. Now, before every drive, I remind myself to be a courteous driver, minimizing unnecessary risks for a more peaceful journey.