BA9S car LED lamp

BA9S LED bulbs (T4W): small size, bright light

The BA9S is a small 9 mm bayonet base, also known as T4W. You will find it in the number plate light, in the position light (parking light) in the headlight and in the interior lighting. Here you will find BA9S LED bulbs in white, daylight white (6000K and 6500K) and blue for 12V, as well as BAX9S versions for number plate lighting, also for 12-24V. All bulbs are supplied in sets of 2.

What to look for when choosing

• Light colour: daylight white or white for number plate and position lights; blue is intended for interior lighting.
• BA9S or BAX9S: on the BAX9S the pins are offset. A BAX9S does not fit a BA9S holder and vice versa.
• Voltage: 12V for passenger cars; the 12-24V version is also suitable for trucks, buses or campers.
• Size: an LED bulb can be slightly longer or wider than the original. Check that there is enough space in the housing.
• Set of 2: replace left and right at the same time so both sides have the same light colour.

Will it fit your car?

Compare with the old bulb: a 9 mm bayonet base with two pins directly opposite each other is a BA9S; offset pins indicate a BAX9S. The bulbs in this collection are not CAN-BUS versions. Do you get a bulb warning on the dashboard after fitting? Then we recommend a suitable resistor; see our LED resistors.

Laws and regulations

If you use these bulbs in the number plate light or position light, the light colour and operation must meet the legal requirements. So check in advance whether use in your vehicle is permitted.

Looking for a different base? Also take a look at the T10 LED bulbs, the C5W 36mm LED bulbs or all LED car lighting.

The tips on this page are non-binding advice; installation and use are at your own expense and responsibility.