Telephone area code 708 covers western and southern Cook County and eastern and southern Will County in the state of Illinois, USA. Area code 708 was split off from area code 312 on November 11, 1989, and once covered almost all of the suburbs of Chicago. In 1996, area code 847 and area code 630 were broken off from 708. Area code 464 is being reserved as an overlay area code for 708 to provide additional numbering options for this area.

Based on this passage, where is area code 708 located in the usa? Let's give stream of consciousness first:
The relevant sentence in the passage is: Telephone area code 708 covers western and southern Cook County and eastern and southern Will County in the state of Illinois, USA.
So, the final answer is western and southern Cook County and eastern and southern Will County in the state of Illinois , USA.