How do I troubleshoot and fix intermittent kitchen light flickering at night?

Short answer

Intermittent flickering at night is usually caused by a loose bulb or connection, an incompatible dimmer with LED bulbs, a failing LED driver, or voltage dips when large appliances cycle on. Start by tightening/replacing the bulb with a quality dimmable LED, test or replace the dimmer with an LED-rated model, and check wiring connections at the switch and fixture (with power off). If the flicker coincides with appliances starting up or voltage readings are low, you may have a circuit or utility voltage issue—call a licensed electrician.

Why lights flicker more at night

• Dimmer and LED mismatch: Older incandescent dimmers don’t regulate LED drivers cleanly, especially at low settings often used at night.
• Weak or failing LED driver/bulb: Budget LEDs have drivers that struggle with minor voltage ripple.
• Voltage dips from appliances: Fridge, well pump, furnace/AC, or dishwasher motors can cause quick sags, more noticeable in quiet evening hours.
• Loose connections: A loose neutral or wirenut in the switch box, fixture, or junction box can cause intermittent flicker.
• Smart switches/bulbs conflicts: Some smart dimmers need a neutral or minimum load; without it, the light may pulse.

Nominal residential voltage: 120 V
Healthy range under load: ~114–126 V (±5%)
Problematic for some LEDs: <110–112 V with sudden dips

Tools and materials

• Non-contact voltage tester and/or multimeter
• Screwdrivers (flat/Phillips)
• Step ladder
• Quality dimmable LED bulbs (Energy Star or DLC listed)
• LED-compatible dimmer (trailing-edge/ELV or listed for LEDs)
• Wire strippers and UL-listed connectors (e.g., Wago 221 lever nuts or quality wirenuts)
• Plug-in voltage monitor (e.g., Kill A Watt) for nearby receptacle
• Flashlight/headlamp

Step-by-step troubleshooting

1. Identify the pattern (5–10 minutes)

   • Does it flicker only when dimmed low? Only at night? When the fridge/HVAC kicks on? On 3-way circuits? Note the behavior before changing anything.

2. Replace the bulb with a known-good, dimmable LED (5 minutes)

   • Use a single brand/model in the fixture. Mix-and-match bulbs can behave differently.
   • If the flicker disappears, the old bulb/driver was the issue. Cost: $5–$15.

3. Tighten the bulb and inspect the socket (5 minutes, power off if inspecting)

   • Power off at the switch. Ensure the bulb is snug, not over-tight.
   • Look for scorched contacts or loose spring tab in the socket. A flattened center contact can be gently lifted with a non-metal tool (power off) to restore tension.

4. Test the dimmer (10–20 minutes)

   • Set the dimmer to full. If flicker stops at full but appears at low levels, you likely have an incompatibility.
   • Temporarily bypass/replace with a standard switch (power off, verify with tester). If flicker stops, install an LED-rated dimmer. Cost: $20–$40; Time: 20–30 minutes.

5. Check switch and fixture connections (20–40 minutes, power off at breaker)

   • Turn off the circuit breaker and verify power is off with a non-contact tester.
   • Pull the switch and inspect connections. Move any “backstabbed” conductors to the screw terminals, or reterminate using proper connectors.
   • At the fixture canopy/box, remake wirenut connections or use lever nuts. Pay special attention to the neutral bundle.

6. Evaluate voltage dips (10–30 minutes)

   • Plug a voltage monitor into a kitchen receptacle on the same circuit, if possible. Observe while the light is on during the usual flicker time.
   • If you see dips under ~112 V when appliances start, redistribute loads (don’t run dishwasher or space heaters on that circuit at the same time) or consult an electrician about circuit separation or service issues.

7. Consider the fixture/driver (15–60 minutes)

   • For integrated LED fixtures or under-cabinet strips, the driver may be failing. Replace with a matching constant-voltage driver (e.g., 12 V DC) with equal or greater wattage and correct dimming type (triac/ELV vs PWM). Driver cost: $15–$40; New fixture: $50–$200.

8. Smart controls check (10–30 minutes)

   • If using a smart dimmer without a neutral, add the required neutral or switch to a model designed for low LED loads. Some systems need a small bypass load to prevent ghosting/flicker—follow the control’s instructions.

Safety

• Always switch off the breaker and verify power is off before opening boxes.
• Do not work in the service panel beyond removing the deadfront; leave feeder/neutral bar checks to a pro.
• Use only UL/ETL-listed components and connectors.

Tips for best results

• Use high-quality, dimmable LEDs and keep all bulbs in a fixture the same brand/model.
• Choose a dimmer specifically rated for LEDs and match the dimmer type to the fixture (leading/trailing-edge, ELV/MLV).
• Set the dimmer’s low-end trim so the light doesn’t run below stable levels.
• Avoid overloading drivers; total LED wattage should be at or below 80–90% of driver/dimmer ratings.

Common mistakes

• Using non-dimmable bulbs on a dimmer.
• Mixing bulb types/brands in the same fixture.
• Leaving backstabbed switch connections instead of using screw terminals.
• Ignoring a suspect neutral—many flicker issues trace back to a loose neutral splice.
• Working live or skipping a voltage check before touching conductors.

When to call a professional

• Flicker affects multiple rooms or circuits, especially at the same time.
• You measure significant voltage swings (<110 V or >126 V) not tied to your own appliances.
• Heat, arcing sounds, or burn marks in boxes or at the panel.
• Aluminum branch wiring or old cloth/Romex wiring you’re not comfortable handling.

Most kitchen flicker problems are solved with a quality bulb and an LED-rated dimmer or by tightening a loose connection. If your observations point to broader voltage instability or panel-level neutrals, bring in a licensed electrician. A typical service call runs $150–$300, and it’s money well spent for safety and reliability.