BMW X2 Tail Light Bulb Size

The BMW X2 tail light requires a P21W bulb size for proper illumination and function. Data provided for the bulb covers the range from 2021 to 2023.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2021-2023	P21W

Description	Bulb Size
ECE standard (Europe & worldwide). Single-filament signalling bulb with BA15s bayonet base. 12V, 21W.	P21W

The P21W is the tail light bulb type specified for the BMW X2 across the 2021-2023 model years.
The P21W operates on a 12-volt electrical system and draws 21 watts, which is standard for single-filament incandescent signalling applications.
The P21W uses a BA15s bayonet base, a single-contact fitting where the "s" denotes a single pin offset to one side of the base, which prevents incorrect installation orientation.
As a single-filament bulb, the P21W is dedicated to one lighting function rather than serving dual roles such as combined stop and tail duties, which require a twin-filament type.
The P21W carries ECE certification, meaning it conforms to the United Nations Economic Commission for Europe lighting regulations accepted across European and numerous worldwide markets.
The BA15s base of the P21W is not interchangeable with the BA15d base, which carries two offset pins. Substituting a BA15d bulb in a BA15s socket is not physically compatible.