For the 2013 Chevrolet Impala, the low-beam headlights use H11 bulbs, while the high beams use H9 bulbs. The daytime running lights also use H9, so confirm which lighting position you are servicing before ordering.
Fog-light fitment is listed with two options: H11 LED and H16 LED. Use the bulb type that matches the existing fog-light housing and connector. The front turn signals and parking lights use 4157NA bulbs, while the front and rear side markers use 194NA.
At the rear, the tail and brake lights use 3057R, the rear turn signals use 3057, and the reverse lights use 921. The center stop light is LED. Interior and utility applications include 578 for the dome and map lights, 912 for the trunk light, and 37 for the vanity light. License-plate, step, ash, and glove-box locations are listed with either 194 or 7441 fitment, so verify the installed bulb before replacement.