You must begin to use the full 10 digits when calling 702 area code numbers beginning Saturday. Calls will not be completed without the 702 area code.

The change is the result of the scheduled area code overlay. Beginning June 3 a new area code will be added to the 702 geographic area. New listings may receive the new 725 area code.

The 702 area code generally covers all of Clark County and principally the greater Las Vegas area. It also serves Boulder City, Henderson, Laughlin, North Las Vegas, Spirit Mountain and Moapa Valley, as well as Mesquite.

A grace period has been in effect since Aug. 3, 2013, when local calls could first be connected using all 10 digits.

In addition to changing dialing procedures, all services, automatic dialing equipment, or other types of equipment that are programmed with a 7-digit number will need to be reprogrammed to use the new dialing procedures. Some examples are life safety systems, PBXs, fax machines, Internet dial-up numbers, alarm and security systems, gates, speed dialers, call forwarding settings, voicemail services, etc.

Emergency calls to 911 will not require the area code.