The Oklahoma Corporation Commission is reminding people who live in the 405 area code that beginning Saturday all calls, even local calls within the same area code, will require dialing the recipient’s area code in addition to the local number.
Local calls within the 405 area code have not previously required the use of an area code when dialing.
In January the OCC voted to add a new area code to the region currently covered by 405.
At the time, officials said the North American Numbering Plan Administrator had determined that the 405 area code would likely run out of telephone numbers by December.
An overlay with an additional area code – 572 – will ensure there area enough phone numbers available.
When the Tulsa area went through a similar process in 2011, businesses were reminded to check their stationary and advertising materials to make sure they included the area code and to ensure all devices and systems that use telephone numbers were set to use 10-digit calling.
The list of systems and equipment potentially impacted included life safety systems, fax machines, alarm and security systems, speed dialers, call forwarding settings, voice mail services and similar functions.
With the widespread use of cell phones instead of landlines, the change may not require as much adjustment for many people when making phone calls but those who use landlines will need to make the change.
Information and assistance calls to services like 411, 211 and 911 will continue to require only three digits.
The telephone system in the 405 has been set to allow either 7 or 10 digit dialing since October 2020. The use of 10 digit dialing becomes mandatory beginning Saturday.
A new 572 area code will be added to the area currently served only by 405 on May 24.
The addition of the new area code will not change existing 405 phone numbers and it won’t change local call boundaries, the OCC said in a release.
“Local calls within the area will remain local calls, regardless of whether the number called is a 405 or 572 area code,” OCC officials wrote.
The region served by the 405 area code isn’t the first in Oklahoma to implement such a change. In 2011, the area served by the 918 area code got an overlay adding the 539 area code for new telephone customers.
In 1998, the 580 area code was added to the state in response to a previous shortage of numbers in the 405 area. Telephone customers outside the Oklahoma City Metro area who previously had 405 numbers had to adjust to a new area code.
At the same time, dialing between Stillwater and the Perkins exchange became a local call. Prior to that, calling between the two towns been billed as long distance.
According to OCC, the 405 area code includes all or portions of Blaine, Caddo, Canadian, Cleveland, Garfield, Garvin, Grady, Hughes, Kingfisher, Lincoln, Logan, McClain, Noble, Okfuskee, Oklahoma, Payne, Pottawatomie, Seminole and Washita counties.