Smart Fortwo high beam and low beam headlight bulbs use 9003 and H7 sizes. The replacement chart covers 2008 to 2018 model years with bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Smart Fortwo uses two distinct bulb types across its headlight specifications: the H7 and the 9003, each serving both high beam and low beam functions depending on the model year.
The H7 is a single-filament halogen bulb operating at 55 watts with a PX26d base, widely used in European vehicle lighting systems. It produces a focused beam pattern suited for dedicated high or low beam applications.
The 9003 bulb, also known as HB2 or H4, is a dual-filament halogen bulb that handles both high and low beam functions within a single unit. It operates at 60 watts on high beam and 55 watts on low beam.
For the Smart Fortwo, the 9003 bulb is specified for both the high beam and low beam positions in 2016-2018 model years, meaning a single bulb type serves both lighting functions in those vehicles.
The H7 bulb is specified for both the high beam and low beam positions across the 2008-2015 model years, indicating that each beam function uses a separate dedicated H7 bulb in a dual-bulb headlight housing.
The H7 and 9003 bulbs are not interchangeable. The H7 uses a PX26d two-pin base, while the 9003 uses a P43t three-pin base, making physical fitment incompatible between the two types without modification.
Because the 9003 is a dual-filament bulb and the H7 is single-filament, substituting one for the other would also result in incorrect electrical behavior, not just a physical mismatch.
The specification shift from H7 to 9003 between the 2015 and 2016 Fortwo model years reflects a change in headlight housing design, as the two bulb types require different mounting configurations.