815 area code is being used for dialing/telecommunication purposes in Illinois, covering 19 major cities and 10 counties, according to (NANP) North American Numbering Plan for 3-digit Numbering Plan Area (NPA) code. All the areas using NPA code 815 is part of CST (Central Standard Time) timezone.
Check this below table to know 19 major cities (having more than 20,000 population) in Illinois using numbering plan area code 815 for dialing/telecommunication purposes.
City | ZIP Codes | Population |
---|---|---|
Belvidere, IL | 1 | 25,389 |
Crystal Lake, IL | 3 | 40,463 |
DeKalb, IL | 1 | 40,697 |
Freeport, IL | 1 | 23,884 |
Joliet, IL | 8 | 150,221 |
Kankakee, IL | 1 | 24,795 |
Lockport, IL | 2 | 26,119 |
Loves Park, IL | 5 | 22,935 |
McHenry, IL | 2 | 27,493 |
Rockford, IL | 14 | 148,173 |
Woodstock, IL | 1 | 26,084 |
815 area code is being used in 10 counties of Illinois for dialing/telecommunication purposes.
1 or more of these 43 NPA codes are being used in the same or adjacent states of Illinois in the United States.