The 331 area code is serving portions of Chicago's near and far western suburbs, including the majority of DuPage County, Illinois. Look up any phone number starting with 331 area code. Results may include:
Federal Data
State Data
County Data
City Data
The 331 area code is often used for fake legal complaint calls and government impersonation scams. Fraudsters pretend to be officials to scare you into handing over money or personal identification.
Scammers from the 331 area code call claiming you have a "complaint on file" that needs your immediate attention. They identify themselves as being from "judicial services" and threaten to report the vague complaint directly to your job's HR or payroll department if you do not update your contact information. They use your fear of workplace embarrassment to pressure you into confirming your name, address, or place of employment. Real legal offices do not call ahead to threaten you. They show up.
"Claim to have a complaint on file and if I do not address the compliant they will contact my HR payroll at work. Go find a job and stop scamming people that work hard for their money."
Callers pretend to be government officials like "Officer Andrew Hall" claiming you have an arrest warrant for tax issues, or people with heavy accents saying there is "suspicious activity" on your Social Security card. They demand you verify your personal information over the phone to avoid arrest or to "unfreeze" your account. They use your Social Security number and other private data to steal your identity or open accounts in your name. Government agencies communicate by mail, not phone calls. They never threaten immediate arrest.
"Officer Andrew Hall said I have an arrest warrant out for me because of suspicious activity on my SS card... need I say more? SCAMMER"
You receive a robocall or voicemail about a large, fake purchase like an "Apple iPhone 16 Pro" costing $999 from Amazon, Walmart, or Apple. The automated message instructs you to press 1 to speak with a representative to cancel the order, then a "support representative" asks for your birthdate or account details to process the fake cancellation. They use these details to access your real accounts or steal your identity. Major retailers send email confirmations for orders, not robocalls asking for personal information.
"They left a voicemail stating to authorize the payment of $999 for the recent order of Apple iPhone 16 Pro on your account. If you do not authorize this payment, please press 1 to speak to our customer support representative."
These are relentless robocalls selling "auto protection" or extended warranties, often claiming your existing one has run out. Some callers know the specific make of your car, such as a "Nissan Versa," to sound more credible. The automated call asks you to "hold on for the next available agent" and they hang up when you try to ask to be removed from their list. They use any information you provide to sell you overpriced, worthless warranties or steal your personal data. Pressing any buttons confirms your number is active and leads to more calls.
"These low-lifes call up hoping to sell you auto protection (after your warranty has run out). I don't have an automobile and I have had so many of their calls that I'm nauseous. Tried being dropped from their call list, and the rep hung up on me."
You get a prerecorded message saying you "qualify for some sort of medical thing" and asking you to participate in a survey. The recording deliberately never mentions the company name but states your answers will not affect your health coverage to make you feel safe. They use any medical or personal information you provide to sell your data to marketers or commit identity theft. Your real doctor's office or insurance provider always identifies themselves immediately when they call.
"no company name as to who is calling and leaving a prerecorded message that will only take a few moment of my time and that anything related to my health coverage no matter the answer will not be affected."
Many reports describe calls from 331 numbers that are completely silent, hang up the moment you answer, or call relentlessly with some residents getting bombarded with up to 7-10 calls in a row from the same number. No voicemail is ever left, even after repeated calls. These calls are made by autodialers to verify that your phone number is active and belongs to a real person. Answering flags your number as "live" and gets it sold to other spammers and scammers.
"I just got 7 calls in row."
Area Code 331 phone numbers reported as unwanted calls to the FTC in the last 30 days.
(331) 207-9599
3 reports ·
(331) 888-9951
2 reports ·
(331) 279-9591
2 reports ·
(331) 293-5459
2 reports ·
(331) 229-0212
2 reports ·
(331) 293-5495
2 reports ·
(331) 215-8583
2 reports ·
(331) 850-9352
2 reports ·
(331) 284-5123
2 reports ·
(331) 348-6832
2 reports ·
No, 331 is a legitimate area code serving the western Chicago suburbs, including Aurora and Naperville. Scammers spoof it to capitalize on its association with affluent Chicago-area communities.
Fake judicial-services calls threatening HR departments and payroll offices to embarrass victims at work are heavily reported. Government agency impersonation claiming arrest warrants under fake badge numbers, and aggressive auto-protection robocalls, are also highly active.
Area code 331 covers a significant portion of the western suburbs of Chicago, Illinois. This includes areas within DuPage, Cook, Kane, and Will counties, as well as a small portion of Kendall County.
Area code 331 is an overlay to area code 630 . Area code 630 was created in 1996. Area code 331 was introduced on October 7, 2007, overlaying area code 630. Ten-digit dialing is mandatory in this area.
Area code 331 is a general purpose code which was placed in service on October 7, 2007.
| Rate Center | Number of Prefixes |
|---|---|
| NAPERVILLE | 12 |
| AURORA | 10 |
| ST CHARLES | 5 |
| DOWNERSGRV | 4 |
| ELMHURST | 3 |
| LEMONT | 3 |
| BARTLETT | 2 |
| BIG ROCK | 1 |
| SUGARGROVE | 1 |
| W CHICAGO | 1 |
| WHEATON | 1 |
| YORKVILLE | 1 |
Browse Illinois area codes for phone number lookup: