Abstract: The present invention comprises a method of managing car wash membership programs that uses unique vehicle identifiers that can be read directly from a vehicle's onboard computer. This method works with vehicles that possess an onboard computer (i.e., “connected cars”) that collects data on the vehicle itself (e.g. vehicle identification number (VIN), oil life, fuel level) and exposes an interface that makes it possible for external systems to request and read this data. An example scenario utilizing this method involves a customer who installs a software application (app) for the car wash on their smartphone. The customer then selects their desired subscription car wash package within the app and the app initiates a communication link directly with the vehicle that will be associated with this membership account.