State regulators are giving central Indiana residents who live in the 317 telephone area code another month before they must begin using 10 digits when dialing.
Ten-digit dialing had been set to become mandatory in the 317 area code on Sept. 17, but the Indiana Utility Regulatory Commission has moved the mandatory start date to Oct. 15.
The commission says it made the move after the Electronic Security Association informed regulators that some home and business security alarm companies were behind in preparing for 10-digit dialing.
Commission members met with alarm company representatives to assess the scope of the situation.
Starting Oct. 15, calls in the 317 area code made with just seven numbers won't be completed and a recording will instruct callers to hang up and dial again.
Regulators say the change is necessary so the new 463 area code can be added to the region this fall.
The new area code will "overlay" the entire 317 region. The 317/463 overlay is being implemented in response to projections that 317 telephone numbers would run out by the end of this year.