Symptoms
- Bulb flickers, blinks, or pulses, especially when dimmed
- Flicker gets worse with certain dimmer settings
- Multiple LED bulbs in the same fixture flicker together
Likely causes
- CommonDimmer switch not rated for LED bulbsOlder dimmers designed for incandescent bulbs often can't smoothly control LED loads and cause flicker.
- CommonA loose bulb or socket connectionLEDs are very sensitive to minor connection issues that incandescents would tolerate fine.
- CommonCheap or low-quality LED bulbsBulbs with poor internal drivers are more prone to visible flicker.
- PossibleVoltage fluctuation on the circuitShared circuits with big appliances can cause visible LED flicker even when incandescents wouldn't show it.
What to do
- Tighten the bulb gently in its socket to rule out a loose connection.
- Try the bulb in a different fixture to see if the flicker follows the bulb.
- If it's on a dimmer, check the dimmer's packaging or label for LED compatibility.
- Replace an incompatible dimmer with an LED-rated model matched to your bulb wattage.
- Try a different brand or higher-quality LED bulb, since cheap bulbs are a common culprit.
- Note if flicker happens when specific appliances turn on, which points to a voltage issue worth having checked.
- Have an electrician check the circuit if flicker continues with quality bulbs and a compatible dimmer.
Tools and parts
LED-compatible dimmer switchSearch: “LED dimmer switch”
Quality LED bulbSearch: “dimmable LED bulb”
When to call a pro
Call an electrician if flicker continues after trying quality bulbs and a compatible dimmer, since it may be a wiring or voltage issue.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.