Effective January 14, 2017, you should start entering the area code for all calls. If you forget and dial just seven digits, your call will still be completed.
Beginning July 8, 2017, you'll need to use the new calling procedure for all calls. On or after this date, if you don't enter the area code + telephone number, your call won't be completed and a recording will instruct you to hang up and dial again.
Beginning August 1, 2017, new telephone lines or services in the former 323 area may be assigned numbers with the 213 area code, and new telephone lines or services in the former 213 area may be assigned numbers with the 323 area code. If you have a 213 or 323 area code, you must enter the area code + telephone number on all calls or the call won't be completed.