All telephone numbers are grouped into zones. All calls between telephone numbers within a standard zone or to telephone numbers in adjoining standard zones are local calls. All other calls are timed, either STD, Pastoral or Community. So a call from the Adelaide zone to McLaren Vale zone is a local call. A list of number ranges belonging to each zone and adjoining zones is filed with the industry regulator, the Australian Communications Authority.
Special arrangements apply for remote customers located in extended zones.
The zoning system is documented in Telstra s Standard Form of Agreement Public Switched Telephone Service section. The Standard Form of Agreement is the official record of the zoning system. Attachment 6 is a list of charging zones and the number ranges in each zone, plus the names of adjoining zones. Attachment 7 is a list of telephone charging precincts, the number ranges in each precinct, and the names of zones which have local call access to the precinct. Telstra has produced maps to illustrate the zoning system.