Business Phone FAQs
Illinois Area Code 10 Digit Dialing Requirement

Beginning February 24, 2023, customers in the 309 area code region may be assigned a number in the new 861 area code when they request new service or an additional line. Customers receiving the 861 area code will be required to dial the area code and phone number for all local calls, just as customers with telephone numbers from the 309 area code do today. The new 861 area code will serve the same geographic area currently served by the 309 area code.