+1 is the first digit of all phone numbers in the United States. The next 3 digits are named the area code, which might be used in exact state or in a specific location of it. Here you can see what area codes are in Illinois, IL.
Area code map for Illinois
All area codes in Illinois map are shown here:
As you can see above, Illinois area code map is divided into several color zones. It means that in different parts of the state spelling of local phone numbers may differ. At the same time there might be a list of area codes which is used in only city, county or other specific location forming an overlay complex for these IL parts.
Color zones are presented only for approximate location’s visualization where the phone numbers with the specified area code are used. In reality, the boundaries may differ or be not so strict.
List of Illinois area codes
217, 224, 309, 312, 331, 447, 464, 618, 630, 708, 773, 779, 815, 847, 872
Why is area codes map needed?
The map of area codes in Illinois is helpful instrument which allows showing the list of phone number’s codes used there. For more detailed information we recommend to use the following searchers:
- Area code lookup by city;
- Area code lookup by digits;
- All US area codes map;
- The list of all area codes by state.
Also you might be interested in full definition of the term “area code”. We’ve written about this in the article “What is an area code?”.