No, you do not need OnStar to use remote start. There are a number of other aftermarket remote start systems available on the market today that don’t require OnStar service. These systems can be installed in just about any car and provide convenience and safety features like unlocking doors, starting your engine from afar, controlling AC/heat settings, activating security alarms and more. Before deciding which system is best for you, consider what features you want it to have as well as how much installation may cost depending on the type of vehicle you own. Some systems even integrate with your smartphone so that you can access them remotely through an app! It's important to note that most aftermarket remote starts require professional installation – if this isn't something that interests or appeals to you then OnStar may be a better option since their services come pre-installed in certain GM models.