In most cars, the license plate (number plate) light uses a 12-volt bulb with a wedge or festoon base—most commonly a wedge-base W5W/T10 type such as 194 or 168. However, some vehicles use different bases, so checking your manual or inspecting the current bulb is essential before buying.
Understanding license plate lighting and bulb options
License plate illumination is a simple, standardized lighting task, but the exact bulb you need can vary by make, model, and year. Below are the main categories you’re likely to encounter when replacing a number plate bulb.
Wedge-base bulbs (T10/W5W, 194/168)
Wedge-base bulbs are the most common choice for license plate lighting. They have a small glass envelope pushed into a wedge-shaped socket and run on 12V DC. In parts catalogs, these are often labeled as W5W or T10, and the same family is sold under 194 or 168 designations.
- Base types: W5W, T10; commonly referenced as 194 or 168 in catalogs.
- Voltage: typically 12V DC.
- Replacement notes: widely available and straightforward to swap in most cars.
Because wedge-base bulbs come in several nearly identical variants, it’s important to confirm the exact base size and voltage for your vehicle before purchasing.
Festoon bulbs
Some vehicles use festoon-style bulbs for license plate lighting. Festoon bulbs are cylindrical glass tubes with contacts at each end and come in standard lengths such as 31 mm or 38 mm. These are typically 12V incandescent, though LED festoon options exist.
- Sizes: common lengths include 31 mm and 38 mm.
- Base: festoon with two contact points at the ends.
- Replacement notes: may require removing a housing or cover to access the bulb.
Because festoon sizes vary, you should measure the current bulb or consult the vehicle’s manual to determine the correct length and type.
LED replacements for license plate lights
LED upgrades are popular for longer life and brighter illumination. They come in wedge-base (W5W/T10) and festoon formats and may need CANBUS resistors to prevent warning messages on some modern vehicles.
- Wedge LED: fits W5W/T10 sockets; consider color temperature (commonly around 6000K for a bright white light).
- Festoon LED: available in 31 mm and 38 mm sizes; verify length and polarity before installation.
- Electrical considerations: some cars require resistors or wiring adapters to avoid bulb-out warnings or abnormal flashing when using LEDs.
LED replacements offer longer life and cooler operation, but compatibility with your vehicle’s electrical system is key to a trouble-free swap.
In practice, most replacement work centers on wedge-base or festoon configurations, with LED options available for both formats.
How to determine the exact bulb for your car
Because base sizes and formats differ across makes, models, and years, the most reliable approach is to confirm the exact specification for your vehicle.
- Check the owner’s manual or a trusted parts catalog for the precise license plate bulb specification for your car.
- Carefully remove the license plate light housing and inspect the bulb’s base or measure its length and socket type.
- Match the measurement and base to a replacement listing (for example, wedge W5W/T10 194/168 or festoon 31/38 mm).
- Purchase the correct base, voltage (12V), and, if upgrading to LED, ensure CANBUS compatibility or plan to add resistors if required.
Taking a moment to verify the exact base type helps prevent incorrect purchases and installation issues.
Practical considerations and tips
- Always disconnect the battery or ensure the ignition is off before handling bulbs to avoid short circuits or shocks.
- If you’re upgrading to LED, be mindful of color temperature and brightness to avoid overly harsh lighting or glare at night.
- Some vehicles require minor wiring changes or resistors when using non-standard LED replacements to prevent warning indicators.
Summary
Most license plate bulbs are 12V and come in wedge-base (W5W/T10, commonly 194/168) or festoon variants, with LED replacements increasingly popular. The exact type depends on the vehicle, so always verify by checking the manual or the current bulb’s base before buying. Replacements are usually straightforward, but LED upgrades may involve resistors or CANBUS considerations on newer cars.
What kind of light do I need for my license plate?
Common U.S. LED License Plate Light Bulb Sizes
In the United States, several bulb sizes are commonly used for license plate lights: 194 (T10): Standard for most vehicles (e.g., Toyota Camry, Honda Accord). 168, 2825: Used in trucks and SUVs (e.g., Ford F-150, Chevy Silverado).
What is the license plate light called?
tag light
The number plate light bulb, also known as the license plate light bulb or the tag light, illuminates a vehicle's rear license plate.
Can I get pulled over if one license plate light is out?
Can you be stopped or ticketed in California for a plate light being out? Yes, you can be stopped, and you may receive a ticket, especially if you are driving after dark. California vehicle rules require that the rear plate is illuminated and legible at night.
What is a number plate bulb?
UK law requires number plate lights to illuminate your rear registration plate sufficiently for reading in darkness. Both bulbs must work if your vehicle has twin lights, and the light must render your number plate visible from a reasonable distance.