Kia Forte Tail Light Bulb Size

The Kia Forte tail light utilizes 12961, 2357, and P21/5W bulb sizes for the rear lighting system. Data for the specified components covers the range from 2010 through 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
2023	12961
2022	2357
2021	P21/5W
2014-2018	2357 (With Halogen Capsule Headlamps)
2010-2013	2357

Bulb Specifications

Description	Bulb Size
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Brighter variant of 1157. 12V, 26.9W/8W.	2357
ECE standard (Europe & worldwide). Dual-filament signalling bulb with BAY15d bayonet base. 12V, 21W/5W.	P21/5W

Other Locations

Additional Notes

The 2357 is the most frequently specified tail light bulb across the Kia Forte lineup, appearing in the 2010-2013 model years without condition and in the 2014-2018 model years specifically under a "With Halogen Capsule Headlamps" fitment condition.
The 2357 is an ANSI-standard dual-filament bulb operating at 12V with a high-filament draw of 26.9W and a low-filament draw of 8W, fitted with a BAY15d bayonet base. It is a brighter variant of the widely known 1157 bulb.
The P21/5W, specified for the 2021 Forte, follows the ECE standard used in Europe and worldwide. It also uses a BAY15d bayonet base and operates at 12V, but its filaments are rated at 21W and 5W rather than the higher wattage of the 2357.
Although the 2357 and P21/5W share the same BAY15d bayonet base, their wattage ratings differ, which is a relevant factor in determining whether one can substitute for the other in a given application.
The 12961, specified for the 2023 Forte, is a Philips part number designating a miniature wedge-type T10 bulb with a W2.1x9.5d base, rated at 12V and 5W. Its base type is physically incompatible with the BAY15d base used by the 2357 and P21/5W.
The 2014-2018 Forte entries carry the qualifier "With Halogen Capsule Headlamps," indicating that the 2357 tail light bulb size applies specifically to that headlamp configuration rather than to all variants of those model years.