What is 309 area code?

The 309 area code is located in the state of Illinois, covering the central portion of the state, including cities such as Peoria, Bloomington, and Rock Island. The 309 area code was created in 1996 as a split from the original 309 area code, which covered the entire state of Illinois. The 309 area code is bordered by area codes 217, 224, 630, and 815. This area code serves a population of over 1.5 million residents.