Does Turning Lights On And Off Shorten Bulb’s Life?

The conventional wisdom we have been using for our light bulbs has changed quite a lot over the past few decades.

Especially since the common and widespread use of LEDs, which are energy-efficient, power-saving, neat little devices that can save the planet.

But also, they work very differently from your traditional incandescent bulbs.

And so its usage, care, and maintenance are also different. An LED is electronic and needs to be used with caution at the end of the day, but LEDs can take a lot more punching before they start to weaken. They are resilient and hardy.

Turning lights on and off weakens all light bulbs. LEDs are affected due to the capacitors facing electrical stress, incandescents weaken due to their delicate filament, and CFLs weaken due to the high start up voltage going through the electrodes.

Does Fast Flipping Of The Switch Reduce Bulbs Lifespan?

As kids, I am sure the majority of us have flipped the light switch on and off quickly to try out the cool flashing effects! I am equally sure we all received a lot of warnings from our parents.

Related: How Far Should The Light Switch Be From The Door?

Well, guess what?

Your parents were absolutely right about not turning the bulb on and off too quickly! The power surge that comes with an LED is switched on and off many times causes electrical overstress (EOS) on the microchips.

Basically, the capacitors are forced to charge and discharge quickly, causing electrical stress.

This stress can cause the lifespan of the LED to be reduced, and the bulb to die off quicker than its average rated life.

Not only the bulb but the wall switch is also being stressed. When current passes through wiring in the circuit of the switch, it starts to heat the wiring. Then, when the current stops flowing, the wires begin to cool down.

When this is done too quickly, without giving the wiring enough time to warm up or cool up, the thermal cycle keeps getting reset, and it will end up damaging the wiring.

Are There Any Other Hazards Of Fast Switching?

So you have seen what can happen to your bulb when you or someone else quickly turns the light on and off. It is just not great for the electricals.

But now, let me tell you how it can also harm you as an individual.

First of all, it’s super annoying. I have not met anyone who likes a light that is being turned on and off quickly. It’s just not something humans are wired to enjoy!

Secondly, some people can be affected more severely. This is especially true for people with epilepsy, who cannot tolerate flashing lights of a certain frequency and end up having a seizure.

Other than that, the only other harmful effect of rapid switching is theoretically, higher electricity bills due to the influx of high voltage. But it is very minimal.

What Types Of Bulbs Are Prone To Get Damaged

burned out light

It is pretty clear that any way you look at it, lights will get damaged by frequently and unnecessarily turning them on and off.

But let’s say you really want to do it! I don’t know why you want that, but I am here to help you reach a compromise.

Different bulb types get affected differently. LEDs, CFLs, and incandescents all get affected differently.

If you insist on fast switching, LEDs will be your best bet. They are least prone to getting damaged as quickly or badly as other types of bulbs.

Incandescents also don’t fare well due to fast switching. The light produced by these bulbs comes from the white-hot glowing tungsten filament held on prongs. When the current is turned on and off, the filament has to quickly heat and cool.

The quick heating and cooling of the filament causes it to get weakened and brittle. It will eventually break soon at the moment you turn it on.

CFLs, lastly, fare the worst when it comes to rapidly turn them on and off. CFLs use a higher voltage to start the light than to run the light. About 1.8 times higher.

This high start-up voltage must start the flow of electrons that then interact with the gases to give light. It is required but not good for the electrodes at the base of the tube. The higher start-up voltage erodes the electrodes every time.

So when a high voltage is pushed multiple times in under 5 minutes, the life of the CFL drops very significantly. If done often, its lifespan may drop from 10,000 hours to about 2,000 hours.

How To Improve The Lifespan Of Light Bulbs?


Let’s figure out how to keep your LEDs and light bulbs running for a long time.

For LEDs, ambient temperature is like their cocoon. They thrive in cool temperatures, and don’t do well in hot areas. This can be hot regions, enclosed fixtures or above the stove scenarios.

Incandescents do well, then they are not used in an area where there are excessive vibrations and force so that the thin filament that produces the light does not get broken.

If the cause of the LED’s lifespan being reduced is the fast switching on and off, then a solution has been introduced.

Thankfully, to prevent the lifespan from being affected much, a lot of LEDs now come with ‘Soft Start,’ whereby the bulb takes a moment to turn entirely on.

Sometimes, it’s just better to leave the bulb on if you need to turn it off just for a little while.

While LEDs are much cooler than other lighting, they still run warm. So the best strategy to keep their lifespan as long as intended is to not allow overheating.

Allowing them to cool off before you turn them on again is a good practice.

Closely in hand to fast switching is a stable current supply. If your area is prone to frequent fluctuations in voltage or current, then the LEDs will be affected.

Installing dynamic voltage stabilizers (Amazon) might do the trick. Not just for your bulbs, but all electronics on the circuit board.

Final Words

So here’s the high and low of switching your light bulb on and off quickly and rapidly. It’s just not great for the well being of the bulb or the user!

Are you worried the kids are turning lights on and off too often?

Have you installed LEDs and reduced your stress about causing damage to the bulbs?

Share your thoughts with me in the comments below.

Looking for an LED bulb but not sure what type you need?

Check out my free bulb picker and select the right bulb within few clicks.