🛈 If you buy through our links, Amazon pays us a small commission at no extra cost to you. That’s how we keep the database running. How we choose.
📑 Contents
⚡ The best C5W bulbs in stock
Stock checked on October 8, 2026
The best C5W bulbs in stock
iBrightstar 9-30V Extremely Bright 6411 6418 C5W Festoon LED Bulbs Error Free 1.5" 36mm for Interior Map Dome…
iBrightstar 9-30V Extremely Bright 6411 6418 C5W Festoon LED Bulbs Error Free 1.5" 36mm for Interior Map…
iBrightstar 9-30V Extremely Bright 6411 6418 C5W Festoon LED Bulbs Error Free 1.5" 36mm for Interior Map Dome…
iBrightstar 9-30V Extremely Bright 6411 6418 C5W Festoon LED Bulbs Error Free 1.5" 36mm for Interior Map Dome…
iBrightstar 9-30V Extremely Bright 6411 6418 C5W Festoon LED Bulbs Error Free 1.5" 36mm for Interior Map Dome…
iBrightstar 9-30V Extremely Bright 6411 6418 C5W Festoon LED Bulbs Error Free 1.5" 36mm for Interior Map…
See more C5W bulbs on Amazon →
LuzCoche score: combines the average rating and the number of customer reviews on Amazon.
Cars that use a C5W bulb
We don’t have any cars with this bulb in our English database yet. Search for your car to see all its bulbs.
Which C5W to buy: standard, brighter or long life
- Standard: the classic incandescent bulb; cheap and no dashboard warnings.
- LED: whiter light and lower power draw. On turn signals and brake lights they can cause hyperflash or bulb-out warnings: choose CANbus versions or add load resistors.
- Long life: handy where bulbs are hard to reach (tail lights or dome lights).
To confirm which bulb each light on your car uses, follow the methods in how to find out which bulb your car takes.
Signal & interior bulbs
Frequently asked questions
What is a C5W bulb?
The C5W is a 5 W, 12 V automotive bulb with a SV8.5-8 base. It’s also sold as 6418 and DE3423.
Is the C5W the same as the P21W?
No. Even if they look alike, each size has a different base (SV8.5-8 on the C5W) and won’t fit another size’s socket. Always buy the exact size your car takes.
Can I replace a C5W with an LED?
Yes, LEDs are common for turn signals, parking, license plate and dome lights. Pick CANbus versions or use load resistors to avoid hyperflash and bulb-out warnings, and keep the correct color (amber for turn signals, red for brake lights).