The answer to 'how long does dimmer switch last' is that a typical dimmer switch can last anywhere from 5 to 15 years with normal use. Dimmer switches are electronic devices that control the amount of electricity flowing to a light fixture, allowing you to adjust the brightness. Over time, the internal components can wear out, especially with frequent use or higher wattage bulbs.
To maximize the lifespan of your dimmer switch, be sure to use it within the recommended wattage range, avoid turning it on and off rapidly, and clean the switch occasionally to prevent dust buildup. If you notice the dimmer switch becoming less responsive or the lights flickering, it may be time to replace the unit.