Below is a list of light bulb types used in 2012-2019 MERCEDES-BENZ CLA-CLASS lighting system, covering estate and coupé vehicles.
Headlight bulb: low beam - H7 or D3S / high beam - H15 or D3S
Parking light bulb: H15
Fog light bulb: H11
Front indicator/turn signal bulb: P21W
Daytime running light bulb: H15
Cornering light bulb: H7
Rear indicator/turn signal bulb: P21W
Tail light bulb: W16W
Brake light bulb: W16W
Back-up light bulb: W16W
Rear fog light bulb: P21W
Interior light bulb: C10W
Boot light bulb: W5W
Entry light bulb: W5W
Footwell light bulb: W5W
Reading light bulb: W5W
Light bulb sizes for other MERCEDES-BENZ CLA-CLASS generations: CLA-CLASS (C118)