Disclosed embodiments include a multi-network gateway system providing one or more third-party telecommunications service providers access to a third-party network interface across an otherwise proprietary access network maintained by a primary telecommunications service provider. Specifically, one embodiment includes an access network provided by a primary telecommunications service provider in communication with a multi-network access gateway. One subset of telecommunications information conveyed across the access network is provided to a customer of the primary telecommunications service provider. Another subset of telecommunications information conveyed across the access network is provided to a third-party network interface and to a third-party network, for the use of the third-party telecommunications service provider.