Everything you need to know about area code 331 in Illinois
QUICK FACTS
Illinois
Central Time Zone
Overlay code
Estimated residents served
Illinois
Shares territory with existing code
ABOUT THIS AREA CODE
Area code 331 is an overlay for the western suburbs of Chicago, sharing coverage with area code 630. It serves DuPage, Kane, and Kendall counties in the rapidly growing exurban region.
Phone numbers with the 331 area code follow the format (331) XXX-XXXX, where the next three digits represent the local exchange. The 331 area code is part of the North American Numbering Plan (NANP) and is regulated by the Federal Communications Commission (FCC).
If you receive a call from a 331 number that you don't recognize, you can search it using the lookup tool above. While the 331 area code legitimately serves millions of residents and businesses in the Aurora area, scammers sometimes spoof local area codes to make their calls appear more trustworthy. Always verify unfamiliar numbers before returning calls or sharing personal information.
The Aurora region served by area code 331 is one of the most significant areas in Illinois. As an overlay code, 331 shares its geographic territory with other area codes in the region, meaning all local calls require 10-digit dialing.
For detailed information about any phone number in the 331 area code, including owner identification, carrier data, and spam reports, use our search tool above or visit one of our trusted lookup providers.
CITIES & COMMUNITIES
SPAM & SCAM ALERTS
These are frequently reported scam patterns from phone numbers using the 331 area code. Scammers often spoof area codes, so a call appearing to come from 331 may originate elsewhere.
Callers impersonate a grandchild in trouble, claiming to need bail money or emergency funds wired immediately.
Automated messages claim a package could not be delivered and direct you to a phishing website to reschedule delivery.
Callers offer fake student loan forgiveness programs, collecting personal and financial information under the pretense of reducing your debt.
Stay Safe: Never share personal information with incoming callers. If suspicious, hang up and search the number above.
FREQUENTLY ASKED QUESTIONS
Area code 331 serves Aurora, Illinois. Area code 331 is an overlay for the western suburbs of Chicago, sharing coverage with area code 630. It serves DuPage, Kane, and Kendall counties in the rapidly growing exurban region.
Area code 331 is in the Central timezone. Calls from 331 numbers originate from the Aurora region.
Not necessarily. Area code 331 serves many people in Aurora. However, scammers can spoof any area code. If you receive a suspicious call from a 331 number, search it above before calling back.
Area code 331 was created in 2007. It is an overlay code sharing territory with an existing area code.
RELATED AREA CODES
WHO CALLED ME
If you received an unknown call from a 331 number, use our dedicated lookup page to identify the caller and check for scam reports.
Who Called Me From 331? →