The passenger compartment of the E-Class remained stable in the frontal offset test. Dummy numbers showed good protection of the knees and femurs of both the driver and passenger. Mercedes-Benz showed that a similar level of protection would be provided to occupants of different sizes and to those sitting in different positions.   Analysis of the deceleration of the impact trolley during the test, and analysis of the deformable barrier after the test, revealed that the E-Class would be a moderately benign impact partner in a frontal collision. In the full-width rigid barrier test, protection was good for all critical body areas of the driver and good or adequate for the rear passenger. In both the side barrier and pole impact tests, protection of all critical body areas was good and the car scored maximum points in this part of the assessment. Control of excursion (the extent to which a body is thrown to the other side of the vehicle when it is hit from the far side) was found to be adequate. The E-Class has a countermeasure to mitigate against occupant-to-occupant injuries in such impacts and this performed well in Euro NCAP's test, with good protection of heads of both front occupants. Tests on the front seats and head restraints demonstrated good protection against whiplash injuries in the event of a rear-end collision.  A geometric analysis of the rear seats also indicated good whiplash protection.   The E-Class has an advanced eCall system which alerts the emergency services in the event of a crash, and there is a system to prevent secondary impacts after the car has been in a collision.

In the both the frontal offset and side barrier tests, protection was good for all critical body areas of both child dummies.  The front passenger airbag is automatically disabled when a child restraint is placed in that seating position. Mercedes-Benz demonstrated that system worked robustly, the airbag being enabled when an adult occupied the seat but being disabled with a child restraint system. The vehicle is equipped with an indirect child presence detection system, which warns when a child or infant may have been left in the car.  All of the child restraint types for which the E-Class is designed could be properly installed and accommodated in the car.

Protection of the head of a struck pedestrian or cyclist was predominantly good, with poor results recorded on the still windscreen pillars and at the base of the screen.  Protection of the pelvis was poor at almost all test locations, while that of the femur and of the knee and tibia was predominantly good.  The autonomous emergency braking (AEB) system of the Mercedes-Benz can respond to vulnerable road users as well as to other vehicles and the system’s response to pedestrians was good.  Likewise, the system performed well in tests of its response to cyclists, scoring almost full points, including for ‘dooring’, where a door is suddenly opened in the path of a cyclist approaching from behind.  Overall, the AEB system performed well in tests of its response to motorcyclists.

Overall, the performance of the autonomous emergency braking (AEB) system was good in tests of its reaction to other vehicles, with collisions avoided in almost all tests.  A seatbelt reminder system is fitted as standard to the front and rear seats.  The car has an indirect driver status monitoring system as standard, detecting driver fatigue.  A direct eye-monitoring system, capable of detecting distraction as well as fatigue, is available as an option.  The lane support system gently corrects the vehicle’s path if it is drifting out of lane and also intervenes in some more critical situations.  The speed assistance system identifies the local speed limit.  The driver can choose to allow the limiter to be set automatically by the system.