The passenger compartment of the EQS remained stable in the frontal offset test. Dummy numbers showed good protection of the knees and femurs of both the driver and passenger. Daimler 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 EQS would be a moderately benign impact partner in a frontal collision. In the full-width rigid barrier test, good protection was provided to all critical body areas of the driver and rear passenger, and the EQS scored maximum points in this part of the assessment.  In both the side barrier test and the more severe side pole impact, protection of all critical body areas was good and the car scored maximum points in this part of the assessment. Limitation of occupant excursion - the extent to which the occupant is flung to the other side of the vehicle in a side impact - was rated as adequate. The EQS is equipped with a centre airbag to protect against occupant to occupant injuries in side impacts. The airbag performed well in Euro NCAP's tests, with good protection of the dummies' heads. 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 car is equipped with an advanced eCall system which automatically alerts the emergency services in the event of an accident.  A multi-collision braking system prevents secondary impacts after the car has been involved in a collision.

In the both the frontal offset test and the side barrier test, protection of all critical body regions was good, for both child dummies.  The front passenger airbag is automatically disabled when a rearward-facing child restraint is put in that seating position. Tests showed that the system worked robustly and the system was rewarded.   All of the child restraint types for which the EQS is designed could be properly installed and accommodated in the car.

The EQS has an 'active bonnet'. Sensors in the bumper detect when a pedestrian has been hit and actuators lift the bonnet to create more space between its surface and the hard components beneath. Daimler demonstrated that the system worked robustly for various pedestrian statures and over a wide range of speeds and, accordingly, the car was tested with the bonnet in the deployed, raised, condition. Protection of the head of a struck pedestrian was good, or at least adequate, over almost the entire area tested by Euro NCAP. Similarly, the bumper provided good protection to pedestrians' legs at all test points. However, pelvis protection was mixed, some test areas showing good protection and some poor. The autonomous emergency braking system of the EQS can detect vulnerable road users such as pedestrians and cyclists, as well as other vehicles. The system performed well in tests of its response to such road-users, with collisions avoided in most cases.

The EQS has a seatbelt reminder system for the front and rear seats. ‘Attention Assist’ monitors steering inputs to detect behaviour characteristic of fatigued driving and advises the driver to rest when necessary. A more advanced system featuring direct eye monitoring is available as an option but was not rated here.  The lane support system gently corrects the vehicle's path when it is drifting out of lane and also intervenes in some more critical situations to stop the car from leaving the road, for example. A speed assistance system uses a camera and digital mapping to determine the local speed limit and provides the information to the driver, allowing the speed limiter to be set appropriately. The AEB system performed well in tests of its reaction to other cars.