A "complimentary subscription" is when you are given something for free, usually a magazine or online service, without having to pay for it. Full definition
REMOTELINK APP Included with a 5 - year complimentary subscription as part of OnStar, RemoteLink allows owners to lock, unlock, activate the lights and horn, and start their car's engine using a simple app on their smartphone. (kbb.com)
Sensus Connect with 6 - month complimentary subscription with unlimited data and in - car Wi - Fi hotspot (bestride.com)
Radio: High Performance Audio System - inc: Sensus Connect w / complimentary subscription for 6 months or 3 GB (whichever comes first), integrated 9 color touchscreen, Bluetooth connectivity, SiriusXM satellite radio w / 6 - month subscription, auxiliary audio input, USB input, 330 - watt amp, (10) speakers, smartphone integration and USB hub (Apple CarPlay / Android Auto) (holmesmercedes.com)