For the 2011 Subaru Impreza, the high-beam headlight uses a 9005 bulb. Low-beam fitment depends on the model and headlight system: the 2.5i Premium uses H11, while the WRX Limited with HID headlights uses a D2S bulb. Confirm the headlight type and trim before ordering.
Exterior lighting also varies by body style and equipment. Front turn signals, parking lights, and front side markers use 1157A. Rear turn signals use 7440A. Reverse-light fitment is 7440 on wagon models, while the other listed configuration uses 921. Sedan brake and tail lights use 7443R, with a 7506 sedan center stop bulb; other listed configurations use LED lighting.
Rear side-marker fitment differs between body styles: sedans use 7443A, while wagons use 168NA. Dome and map lights use DE3175. License-plate lighting is listed as 168 or 917, so compare the original bulb where alternatives are shown.