331 Area Code
Illinois, USA
Local time now · Central Time
2:42 AM
Area code 331 is in Illinois, USA, serving Carol Stream, Streamwood, St. Charles and Bensenville. It uses Central Time — the time there now is 2:42 AM. 630 is an overlay for the same area, so local calls need 10-digit dialing. In service since 2007.
| Area code | 331 |
|---|---|
| Location | Illinois, USA |
| Major cities | Carol Stream, Streamwood, St. Charles, Bensenville, Lemont, Wood Dale |
| Time zone | Central Time |
| Overlay codes | 630 |
| In service since | 2007 |
Other area codes in Illinois
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Frequently asked questions
Where is area code 331?
Illinois, USA — including Carol Stream, Streamwood, St. Charles, Bensenville and Lemont.
What time zone is area code 331?
Central Time.
How do I call a 331 number from abroad?
Dial your international access code, then 1 (the country code), then 331 and the 7-digit number — for example +1 331 555 0100. From the UK or India dial 00 1 331 …; from Bangladesh 00 1 331 … .
Is a call from 331 a scam?
Not by itself — 331 is an ordinary geographic area code in Illinois. Numbers can be spoofed, so be careful with unexpected calls asking for money or personal details.
Sources: North American Numbering Plan Administrator (NANPA) NPA database (10/25/2026); major cities from Wikidata (CC0). An area code shows where a number was first assigned — with number portability and mobile phones, the caller may be anywhere.