The present invention provides a method for managing mobile handset portability within a telematics equipped mobile vehicle. The method includes assigning a primary telematics unit identifier to a user account, assigning the primary telematics unit identifier to a mobile handset, associating the mobile handset with any one of a plurality of telematics units operating within the mobile vehicle communication system, and operating the associated telematics unit. The step of associating the mobile handset may include coupling the mobile handset to the telematics unit, communicating the assigned telematics unit identifier of the mobile handset to a service provider, and downloading user preferences from the service provider wherein the user preferences are based on the user account associated with the communicated telematics unit identifier. The step of downloading the user preferences may include determining the user preferences at the service provider and receiving the user preferences from the service provider.