The Indiana Office of Utility Consumer Counselor says everyone in central Indiana's 317 telephone area code must use 10 digits for all local telephone calls in less than two weeks.
It says Saturday, Oct. 15, will mark the end of a seven-month grace period in which local calls could be completed with either seven or 10 digits.
A new area code will overlay the entire 317 region that includes Indianapolis and most of its suburbs. Beginning in mid-November, newly assigned telephone numbers may have a 463 area code.
People trying to complete a local phone call with seven digits on or after Oct. 15 will hear a recording prompting them to retry the call with the 317 area code included.