What is what area code is 309?

Area code 309 is a telephone area code in the North American Numbering Plan (NANP) for the state of Illinois in the United States. It covers the central and west-central part of the state including cities such as Peoria, Bloomington, Moline, and Rock Island. Area code 309 was established in 1957 as one of the original area codes in Illinois. It was split off from area code 217 which previously covered the entire state.

Some of the major cities and communities served by area code 309 include East Peoria, Galesburg, Normal, Pekin, East Moline, and Washington. The area code covers a total of 24 counties in Illinois.

In addition to traditional landline phones, area code 309 is also used for cell phones, fax machines, and other telecommunications devices. It is one of the main area codes used throughout central Illinois and is an important part of the state's telecommunications infrastructure.