Both the S60 and C-Class Sedan have child safety locks to prevent children from opening the rear doors. The S60 Plus/Ultimate/Polestar has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The C-Class Sedan’s child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.
The S60’s lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane and gently nudges the vehicle back towards its lane. The C-Class Sedan doesn’t offer a lane departure warning system.
To help make backing out of a parking space safer, the S60 has a standard rear cross-path warning system, which uses sensors in the rear bumper to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. Rear cross-path warning costs extra on the C-Class Sedan.
Both the S60 and the C-Class Sedan have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, front and rear seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, post-collision automatic braking systems, daytime running lights, blind spot warning systems, rearview cameras, driver alert monitors, available all wheel drive and around view monitors.

