The Kia Rio tail light utilizes 1157, 921, and PY21W bulb sizes for various lighting components located at the rear of the vehicle. Data for the specified bulb sizes covers the range from 2001 through 2023.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 1157 bulb is the most frequently listed size across the Kia Rio tail light specifications, appearing in the outer tail light position for model years 2001-2002 and 2006-2011. It follows the ANSI standard used in the US and Canada, operates at 12V, and carries dual filaments rated at 21W and 5W, with a BAY15d bayonet base.
The P21/5W bulb shares the same BAY15d bayonet base and 21W/5W dual-filament configuration as the 1157, but it follows the ECE standard used in Europe and worldwide rather than the ANSI standard. Both types are therefore electrically similar despite originating from different standardization systems.
The Kia Rio outer tail light for 2019-2020 specifies the P21/5W exclusively under the condition of halogen capsule headlamps, indicating that the headlamp type on the vehicle determines which tail light bulb applies.
The 12961 is a Philips part number for a miniature wedge bulb of the T10 form factor, using a W2.1x9.5d base and rated at 12V, 5W. It is specified for the inner tail light position on the 2019-2020 Kia Rio, again restricted to vehicles with halogen capsule headlamps.
The PY21W is a single-filament amber bulb with a BAU15s bayonet base, rated at 12V and 21W. Its BAU15s base is offset compared to the BAY15d base found on the P21/5W and 1157, making these bulb types physically non-interchangeable despite similar wattage ratings.
The 921 is an ANSI-standard wedge bulb of the T15 form factor, rated at 12V and 16W. It uses a wedge base rather than a bayonet fitting, which distinguishes it physically from the dual-filament bayonet-based bulbs listed elsewhere in the Rio specifications.
The outer tail light position on the 2019 Kia Rio lists two different bulb sizes across separate entries: P21/5W for vehicles with halogen capsule headlamps and 921 for a separate configuration, indicating that fitment varies depending on the specific equipment level of the vehicle.