To faciltiate users, the United States of America is divided into regions known as Area Codes, corresponding to particular geographic telephone dialing areas.
An area code denotes the regional location of a phone number within the United States.
The Area Code table below shows an area codes each.
Area Code 331 listing, by city
@The cities listed with each area code are the major cities for that area code;
| City / State | Area code | Zip Code | County | Iso | |
|---|---|---|---|---|---|
| Homer Glen (Illinois) | 331 | 60491 | Will | US-IL | |
| Roselle (Illinois) | 331 | 60172 | DuPage | US-IL | |
| Saint Charles (Illinois) | 331 | 60175 | Kane | US-IL | |
| Sugar Grove (Illinois) | 331 | 60554 | Kane | US-IL | |
| Wheaton (Illinois) | 331 | 60189 | DuPage | US-IL |