A host-sponsored data transmission billing system and method is provided to permit reduced costs to a mobile user for internet access through an internet gateway. An operator billing system is provided (either in the internet gateway itself or coupled to the internet gateway) to generate billing data for payment by the mobile user for connection requests by the mobile user through the internet gateway to private sites on the internet. However, to reduce the costs to the mobile user to encourage access to host-sponsored commercial sites, the operator billing system bills data for payment by host-sponsors for connection requests by the mobile user to the host-sponsored sites. A General Packet Radio System (GPRS) can be utilized in this arrangement as the internet gateway.