About smart dialling
You can change smart-dialling options to specify a default country code and area code for phone numbers. If you specify a default country code and area code, when you make calls, you only need to dial a country code and area code when the codes differ from the codes that you specified in the smart-dialling options.
In the smart-dialling options, you can also specify the main phone number for an organisation that you call frequently. If you specify a phone number for an organisation, you can call a contact at the organisation quickly by dialling the contact's extension only. Likewise, when you add a contact from the organisation to your contact list, you only need to type the contact's extension.