The state is implementing two new area codes to keep up with a growing supply of telephone numbers and is changing the way phone customers need to dial to complete a call.

Beginning November 14, callers must dial the area code plus telephone number in order to complete a call, even if it is a local call. Calls made with the old seven-digit dialing will not be completed and a recording will instruct the caller to hang up and dial again using 10 digits.

Beginning December 12, new telephone lines or services may be assigned numbers with the 475 area code in areas now served by a 203 area code, which includes Meriden, Wallingford and Cheshire. Existing customers with a 203 area code will not see their phone numbers change.

The 959 area code, which will be assigned to new numbers within the current 860 area code, which includes Southington, will be assigned at a later date. Existing customers with a 860 area code will not see their phone numbers change.