(St. Francois County, MO) Officials with the Missouri Public Service Commission, the North American Numbering Plan Administrator, and the telecommunications industry remind customers to prepare for 10 digit local dialing and the introduction of the new 235 area code in the current 573 area code in Missouri. The 235 area code will be added as an overlay to the 573 region. An overlay does not require customers to change their existing area code, but does require customers to dial the area code to complete local calls. Beginning Saturday, February 24th, all local calls made within the 573 area code must be placed using 10 digits. On and after February 24, 2024, any calls placed using just 7 digits will not be completed. Starting on March 24, 2024, new telephone lines or services may be assigned numbers using the new 235 area code.