What area code is 331?
Here's everything about it.
Instant lookup for the 331 area code — location, time zone, cities served, and who's been calling from it. No sign-up, no app.
331 at a glance
Summary
Cities & regions served by 331
Aurora (overlay)Showing 12 of 68 recorded communities — major cities first.
Where 331 sits on the map
Overlay of 630Coverage area
About the 331 region
331 covers Aurora in Illinois, including Addison, Bartlett, Batavia, Bensenville and Big Rock. The code has been in service since 2007.
331 itself is an overlay: it shares its territory with 630 and was introduced when those codes ran low on new number combinations. New lines may receive either code, calls between them are local, and 10-digit dialing is required across the region.
Overlaid on 630.
Who called me from 331?
Community reports- Caller ID is trivially spoofed: an incoming call that displays 331 does not prove the caller is really in the 331 region or even in the United States.
- Avoid calling back unknown one-ring numbers — some premium-rate scams rely on curiosity callbacks.
- Never share verification codes, payment details, or remote access during an unsolicited call, even if the caller claims to be your bank or a government agency.
- When a 331 call pressures you to act immediately, hang up and contact the organization directly through its official number.
Be the first to add a community report for a 331 number below.
Frequently asked questions
FAQWhat area code is 331?+–
331 is a telephone area code serving Aurora in Illinois, United States, in service since 2007.
Where is area code 331 located?+–
It covers DuPage County, including Addison, Bartlett, Batavia, Bensenville and Big Rock in Illinois.
What cities are in area code 331?+–
Major communities on record include Addison, Bartlett, Batavia, Bensenville and Big Rock, among others. The code's territory spans the Aurora region of Illinois.
What time zone is 331?+–
331 observes Central (CT), which is UTC−6 / −5 DST and follows daylight saving time.
When did area code 331 start?+–
331 entered service in 2007. Its history: overlaid on 630.
Why does area code 331 exist?+–
331 is an overlay of 630: it covers the exact same territory and was introduced when the original code ran low on new number combinations. New lines may receive either code, calls between them are local, and 10-digit dialing applies.
Is 331 a scam area code?+–
Scam and robocall traffic can use any North American code, 331 included — caller ID is easy to spoof, so the code alone does not tell you who is really calling. Check the community reports on this page before calling back an unknown 331 number, and report anything suspicious.
Can I get a 331 phone number?+–
Yes — most mobile carriers and VoIP providers let you request a 331 number regardless of where you physically live, although in an overlaid region you may be assigned 630 instead.