Are you referring to a public membership such as a discounted rate for transport? Please clarify.
Locally, our service (a Public Utility Model) has an annual membership program for the community. It's offered once per year, cost $59/yr. The basic principle is simple. Should your primary insurance carrier deem the transport necessary, the program will cover the deductible. However, should the carrier deny the claim, the membership program will NOT pay and the patient will still receive the entire bill. If you would like to contact me offline, I can forward information as an example.
John Legg
National EMS Association