Numerous occupant protection systems can significantly reduce the risk of injury during an accident. Examples include the NECK-PRO head restraint, a standard feature on the front seats: when the sensor detects an impact from the rear, it thrusts the head restraint forward and upward in a matter of a few milliseconds to reduce the gap between it and the occupant’s head.

The C-Class is also equipped with belt tensioners on the front seats and the outer rear seats and with many airbags, including two-stage driver and front-passenger airbags, sidebags and windowbags extending over all the rows of seats, whose protection zone covers virtually the entire area of the side windows. The sidebags and windowbags are controlled by pressure sensors: if the door deforms in a side-on collision, the increase in air pressure between the body panels and the interior of the door is registered by the pressure sensors, assisting the control unit with deployment of the airbags.

Furthermore, other road users are also protected by means of the body's smooth surfaces and its excellent programmed yielding characteristics.