Telephone numbers in Australia plan (including the "Trunk Access Code"), presented in domestic format. (Geographical region boundaries do not exactly follow State borders.) The current numbering plan would appear to be sufficient to cope with potential increase in demand for services for quite some time to come. The 06 and 09 area codes are completely unused. In addition, each current area code has large number "ranges" unallocated. When dialling from outside Australia, after dialling the appropriate International Access Code it is necessary to dial the Country Code for Australia (61) followed by the nine digit "National 'Significant' Number". (The + symbol is used to
Area code 868 as if undertaking regular ten-digit dialling within those countries. Callers must simply dial 1 + 868 + seven digit phone number. When calling to Trinidad and Tobago from outside the NANP (e.g., from the United Kingdom), callers must dial their international dialling prefix followed by 1 to access the North American Numbering Plan. For example, a call placed from the United Kingdom would be dialled as 00 + 1 + 868 + local seven digit phone number. When placing a phone call from Trinidad and Tobago, also known as HNPA (home numbering plan area) dialling, callers simply use seven-digit dialling