464 Area Code – Cicero, Illinois: Location, Time Zone & History

Few overlay codes have as long a gestation as 464. Its home territory traces back to November 11, 1989, when area code 708 was created in a split from 312 to serve Chicago's southern and western suburbs. That footprint shrank twice in 1996, as 847 took the northern suburbs in January and 630 took the western suburbs that August. NANPA reserved 464 for future relief of 708 as early as June 30, 1999, but the overlay sat unused for more than two decades. It finally went into service on January 21, 2022, alongside newly mandatory ten-digit dialing across 708 and 464 that had been required by October 24, 2021, a shift driven in part by a conflict between the national 988 Suicide Prevention Lifeline and existing 708-988 exchange numbers.

Cicero, the largest municipality in the territory after Chicago itself, anchors the region alongside Berwyn, Oak Lawn, Tinley Park, Orland Park, and Oak Park. Notably, Cicero was the base of Al Capone's organized-crime operations in the 1920s after he relocated there from downtown Chicago.

The area's economy centers on freight rail and logistics, including Canadian National's Markham Yard, one of the Midwest's largest freight classification facilities, alongside manufacturing, healthcare systems such as Advocate Christ Medical Center in Oak Lawn, retail and commercial suburban centers, and warehousing tied to Chicago's expressway network.