Calls from 331 normally come from Illinois — 22 cities across 5 counties, in the Central time zone. Our archive holds 407 caller reports on 141 numbers in this area code.
An area code only tells you the region. Search the full number to see listings and reports for it.
Area code 331 serves Illinois, covering Aurora, Naperville, Geneva, Downers Grove, Elmhurst. In total our directory records 800 phone prefixes in this area code, spread across 22 cities and 5 counties.
The area code sits in the Central time zone (UTC-06:00), where the local time is now approximately 2:41 PM. The oldest prefix on record here entered service on 2007-07-06, and the newest on 2015-09-16.
Of the prefixes with a known line type, 64% are wireless and 36% landline — 55 mobile against 31 fixed-line prefixes.
Illinois is highlighted below. Schematic map — each square is one state or territory.
Telephone companies holding prefixes in this area code, ranked by how many they operate.
Places served by this area code, with the number of prefixes assigned to each.
Aggregated from 407 reports covering 141 distinct numbers in this area code (2015–2017 archive).
Prank Call89Telemarketer57Debt Collector27SMS12Political Call10Non-profit Organization6Unknown5Survey1
331-205-790713 reports331-322-733910 reports331-305-419810 reports331-200-712510 reports331-076-49619 reports331-087-49129 reports331-146-48179 reports331-425-60299 reports
Names people entered when reporting a call from this area code.
Unknown ×11Credit One Bank ×9Credit One ×5n/a ×5Unavailable ×4Americans for Prosperity ×4Illinois call ×4ASSIST ×3Verizon ×3Google ×3unk ×3cricket ×3
Each number below was reported by someone who received a call from it. “Reported as” is the name the caller gave or that the recipient recognised — what people wrote down, not verified ownership.
| Number | Reports | Call type | Reported as | Last report |
|---|---|---|---|---|
| 331-205-7907 | 13 | Prank Call, SMS | (Curatio) Helathcare (I) Pvt. Ltd) / 3312057907 unknown / Curatio Healthcare Pvt. Ltd. / Evergreen Solar Systems Pvt Ltd | 2016-04-09 |
| 331-322-7339 | 10 | Prank Call | individuals / NAPIER ILLINOIS NUMBER | 2016-02-20 |
| 331-305-4198 | 10 | Telemarketer | ASSIST / Don't know / Google / Google Placement Scam | 2016-04-25 |
| 331-200-7125 | 10 | Telemarketer | ? / ??? / ASSIST / Google | 2016-04-11 |
| 331-076-4961 | 9 | Prank Call | cricket / Verison | 2016-04-26 |
| 331-087-4912 | 9 | Prank Call, Survey | Time Warner | 2016-02-29 |
| 331-146-4817 | 9 | Prank Call | No idea / somewhere in Mexico / Verizon | 2016-05-01 |
| 331-425-6029 | 9 | Non-profit Organization, Telemarketer | Breas Cancer An / Breast cancer / Breast Cancer AM / Breast Cancer Am. | 2016-04-30 |
| 331-212-8091 | 9 | Non-profit Organization, Telemarketer | "Unavailable" / ? / Aurora / Call Center | 2016-03-18 |
| 331-976-2746 | 7 | Prank Call | unanimus caller | 2016-03-09 |
| 331-951-4531 | 7 | Prank Call | — | 2016-04-24 |
| 331-949-3337 | 7 | Prank Call | "family member" / ortega | 2016-05-01 |
| 331-701-2995 | 7 | Political Call, Telemarketer | ??? / contact center / pro life / UNK | 2016-04-26 |
| 331-701-2980 | 7 | Telemarketer | DF KING / I dont know / NO ID Illinois / unk | 2016-02-21 |
| 331-472-3243 | 7 | Political Call, Telemarketer | Americans for Prosperity / CELLULAR CALL / telemarketers | 2016-04-29 |
| 331-248-4740 | 7 | Debt Collector, Telemarketer | didnt say / Unknow / unknowne | 2016-04-29 |
| 331-212-8538 | 7 | Telemarketer | Harrassment / Linked Now Media / LinkedNow Media / linknow | 2016-03-30 |
| 331-926-4015 | 6 | Prank Call | — | 2016-04-16 |
| 331-076-7025 | 6 | Prank Call | Not sure | 2016-04-25 |
| 331-111-7608 | 6 | Prank Call | Name Not Found | 2016-02-18 |
| 331-281-3800 | 6 | Debt Collector | BMO bank / BMO Harris / claimed to be BMO Harris but was not / faux-BMO Harris Bank | 2016-02-24 |
| 331-229-5205 | 6 | Debt Collector | Credit One / Credit One Bank / don't know who | 2016-04-20 |
| 331-229-5199 | 6 | Debt Collector, Telemarketer | bank one / CREDIT ONE / Credit one bank | 2016-04-10 |
| 331-229-5197 | 6 | Debt Collector | Credit One / Credit One Bank / IQOR USA | 2016-04-19 |
| 331-215-7291 | 6 | Telemarketer | Corporations for charcter - returning veterans / Veterans Now / VETS NOW | 2016-03-18 |
| 331-003-3527 | 5 | — | century link / cox / family | 2016-03-06 |
| 331-999-1769 | 5 | Prank Call, SMS | Craigslist Scammer / Handman | 2016-01-25 |
| 331-925-3984 | 5 | Prank Call | at&-t / Att / none given / T-Mobile | 2016-03-31 |
| 331-924-9261 | 5 | Prank Call | 5,2812E+11 / house phone | 2016-04-22 |
| 331-291-1631 | 5 | Prank Call | — | 2016-04-09 |
| 331-212-8092 | 5 | Telemarketer | IL Police Chiefs Association / Illinois Call / V220154943003994 / V2201815360040421034? | 2016-04-10 |
| 331-000-1952 | 5 | Prank Call | 5,21332E+12 / Extorsionistas / Operadora unefo | 2016-04-16 |
| 331-701-2998 | 4 | Telemarketer | Security alarm | 2016-04-12 |
| 331-803-1506 | 4 | Prank Call | cricket / Did not say / Mexico number | 2016-04-11 |
| 331-807-6396 | 4 | — | Cox / Not found | 2016-03-28 |
| 331-959-8111 | 4 | Prank Call | displays phone number | 2015-12-25 |
| 331-030-9002 | 4 | — | movistar / relative* | 2016-04-25 |
| 331-146-5707 | 4 | Prank Call | David / SC | 2016-02-07 |
| 331-954-5213 | 4 | Prank Call | +52 (33) 1954 5213 / FRAUD CALL - NO NOT ANSWER | 2016-04-01 |
| 331-256-1080 | 3 | Telemarketer | it wont give me a name / unk | 2016-02-05 |
| 331-253-2543 | 3 | Telemarketer | AC / ac market | 2016-02-11 |
| 331-684-8335 | 3 | Political Call, Prank Call | Aurora | 2016-04-14 |
| 331-807-1662 | 3 | — | — | 2016-02-14 |
| 331-205-7256 | 3 | Debt Collector | +1 (331) 205-7256 Aurora, IL / Unknown from Illinois | 2016-02-02 |
| 331-208-5495 | 3 | Telemarketer | +1 (331) 208-6239 | 2016-04-03 |
| 331-956-4280 | 3 | Prank Call | personal phone call | 2016-05-02 |
| 331-394-4332 | 3 | Prank Call | — | 2016-04-20 |
| 331-991-8364 | 3 | — | 5,23222E+11 / 5,2332E+11 | 2016-03-01 |
| 331-958-8785 | 3 | — | Na | 2015-12-22 |
| 331-212-8086 | 3 | Political Call | Illinois call / unknowed | 2015-12-31 |
| 331-960-1598 | 3 | — | No company identified / unkown | 2016-03-14 |
| 331-212-8132 | 3 | Non-profit Organization | Illinois police assoc / Illinois Police Chiefs Association / UNKNOWN NAME | 2016-02-28 |
| 331-333-6242 | 3 | Debt Collector | sl programs | 2016-03-30 |
| 331-974-2861 | 3 | Prank Call | Out Of Area / Scammer | 2016-01-24 |
| 331-330-4976 | 2 | Telemarketer | ?? / IDT Energy | 2016-04-07 |
| 331-422-3504 | 2 | Debt Collector | Pretrial Mediation Services | 2016-04-05 |
| 331-642-0893 | 2 | — | Agent Raymond / through face book claiming to be a friend | 2016-04-20 |
| 331-212-8093 | 2 | Telemarketer | Scammers INC. | 2015-11-08 |
| 331-454-5801 | 2 | Prank Call, Telemarketer | Aurora, IL = Scammers? | 2015-09-21 |
| 331-425-4061 | 2 | Unknown | — | 2016-04-20 |
Showing the 60 most-reported of 141 numbers on record for this area code.
Our business records list 289 companies reachable on a 331 number, across 63 cities and 190 lines of business. If an unexpected call came from this area code, it may well be one of them.
-- 25Cleaning Services 7Design Services 5Decontamination Services 5Carwashes 4Services, Nec 4Real Estate 4Repair Services, Nec 3General Practice Attorney, Lawyer 3Building Cleaning Service 3Beauty Shops 3Garden Services 3Local Trucking, Without Storage 3Nonresidential Building Operators 3Furniture Stores 3
Headcount and founding year are as recorded in the business register, and a business may hold a number outside the state it operates in.
| Business | Phone | City | Industry | Staff | Founded |
|---|---|---|---|---|---|
| Elmhurst Memorial Hospital Inc | 331-221-1000 | Elmhurst | General Medical And Surgical Hospitals | 2,429 | 1926 |
| Navistar International Corporation | 331-332-5000 | Lisle | Manufacturing - Truck And Tractor Truck Assembly | 1,000 | 1993 |
| Navistar, Inc. | 331-332-5000 | Lisle | Motor Vehicles And Car Bodies | 200 | 1965 |
| Mid-Valley Special Education Joint Agreement | 331-228-4873 | Saint Charles | Specialty Education | 178 | 1972 |
| St Charles Community Unit School District 303 | 331-228-3700 | Saint Charles | Public Junior High School | 145 | — |
| Navistar, Inc. | 331-332-5000 | Joliet | Motor Vehicles And Car Bodies | 140 | — |
| McCandless Truck Center, LLC | 331-332-5000 | Aurora | Wholesale - Truck Parts And Accessories | 135 | 1999 |
| Biggers Chevrolet | 331-551-6617 | Elgin | New And Used Car Dealers | 100 | — |
| ServiceMaster Commercial Office Cleaning Services | 331-305-6028 | Hillside | Building Cleaning Service | 58 | 1952 |
| Reliance Gear Corporation | 331-225-2195 | Addison | Manufacturing - Gears, Power Transmission, Except Auto | 56 | 2011 |
| Elmhurst Memorial Healthcare | 331-221-1000 | Elmhurst | Health Maintenance Organization | 53 | 2013 |
| Stenzel Clinical Services Ltd | 331-472-4043 | Naperville | Services, Nec | 48 | — |
| Community Physical Therapy | 331-248-2694 | Addison | Physical Therapist | 40 | — |
| Aurora West School District 129 | 331-431-7234 | North Aurora | Public Elementary School | 38 | — |
| South Water Signs, LLC | 331-225-3064 | Elmhurst | Signs And Advertising Specialties | 36 | 2006 |
| JC Cross Co. | 331-472-6075 | Romeoville | Garden Services | 31 | — |
| Comprehensive Clinical Services, P.C. | 331-551-6423 | Lombard | Family (marriage) Counseling | 28 | 2000 |
| Univar Inc. | 331-777-6000 | Downers Grove | Industrial Chemicals | 25 | 1986 |
Naperville 56Aurora 32Geneva 28Elmhurst 13West Chicago 11Lisle 10Plainfield 8Saint Charles 8Chicago 8Oswego 7Addison 7Downers Grove 6Bolingbrook 6Lombard 5Villa Park 5Woodridge 5Elgin 4Montgomery 4St. Charles 3Carol Stream 3
Postal codes recorded against prefixes in this area code.
6010360119601266013360134601486015160172601746017560185601876018960439604406049160505605066051160512605156051660517605386054060543605456055460555605606056360565
Each prefix (the first three digits after the area code) is assigned to a carrier and a service area. Showing the first 200 of 800.
| Prefix | City | County | Carrier | Type | In service |
|---|---|---|---|---|---|
| 331-200 | Hanover Park | Cook | T-Mobile Usa, Inc. | Wireless | 2011-07-11 |
| 331-201 | Downers Grove | Dupage | Cellco Partnership Dba Verizon Wireless | Wireless | 2012-01-06 |
| 331-202 | Elmhurst | Dupage | Sprint Spectrum L.p. | Wireless | 2012-01-17 |
| 331-203 | Aurora | Kane | Sprint Spectrum L.p. | Wireless | 2011-10-12 |
| 331-204 | — | — | — | — | — |
| 331-205 | Aurora | Kane | T-Mobile Usa, Inc. | Wireless | 2011-10-21 |
| 331-206 | Aurora | Kane | Sprint Spectrum L.p. | Wireless | 2011-10-12 |
| 331-207 | Yorkville | Kendall | Level 3 Communications, Llc | Landline | 2011-11-01 |
| 331-208 | Aurora | Kane | Sprint Spectrum L.p. | Wireless | 2011-11-08 |
| 331-209 | Elmhurst | Dupage | Level 3 Communications, Llc | Wireless | 2012-01-17 |
| 331-210 | Geneva | Kane | Peerless Network Of Illinois, Llc | Landline | 2012-03-06 |
| 331-211 | — | — | — | — | — |
| 331-212 | Aurora | Kane | Mci Worldcom Communications, Inc. | Landline | 2012-04-05 |
| 331-213 | Naperville | Dupage | Cellco Partnership Dba Verizon Wireless | Wireless | 2011-09-06 |
| 331-214 | Downers Grove | Dupage | Cellco Partnership Dba Verizon Wireless | Wireless | 2012-06-20 |
| 331-215 | Naperville | Dupage | Cellco Partnership Dba Verizon Wireless | Wireless | 2012-09-28 |
| 331-216 | Oswego | Kendall | New Cingular Wireless Pcs, Llc | Wireless | 2012-10-31 |
| 331-217 | — | — | — | — | — |
| 331-218 | Wheaton | Dupage | T-Mobile Usa, Inc. | Wireless | 2013-07-09 |
| 331-219 | — | — | — | — | — |
| 331-220 | Aurora | Kane | Sprint Spectrum L.p. | Wireless | 2011-07-12 |
| 331-221 | Elmhurst | Dupage | Ameritech Illinois | Landline | 2009-01-21 |
| 331-222 | Geneva | Kane | New Cingular Wireless Pcs, Llc | Wireless | 2008-10-28 |
| 331-223 | Geneva | Kane | New Cingular Wireless Pcs, Llc | Wireless | 2008-10-28 |
| 331-224 | — | — | — | — | — |
| 331-225 | Elmhurst | Dupage | Sprint Spectrum L.p. | Wireless | 2011-08-22 |
| 331-226 | — | — | — | — | — |
| 331-227 | — | — | — | — | 2011-08-11 |
| 331-228 | Geneva | Kane | Ovation Communications Of Illinois, Inc. | Wireless | 2011-09-21 |
| 331-229 | Naperville | Dupage | Cellco Partnership Dba Verizon Wireless | Wireless | 2012-11-27 |
| 331-230 | — | — | — | — | — |
| 331-231 | — | — | — | — | — |
| 331-232 | — | — | — | — | — |
| 331-233 | — | — | — | — | — |
| 331-234 | Sugar Grove | Kane | Cellco Partnership Dba Verizon Wireless | Wireless | 2013-07-08 |
| 331-235 | — | — | — | — | — |
| 331-236 | — | — | — | — | — |
| 331-237 | — | — | — | — | — |
| 331-238 | — | — | — | — | — |
| 331-239 | — | — | — | — | — |
| 331-240 | West Chicago | Dupage | Peerless Network Of Illinois, Llc | Landline | 2013-04-10 |
| 331-241 | — | — | — | — | — |
| 331-242 | — | — | — | — | — |
| 331-243 | — | — | — | — | — |
| 331-244 | — | — | — | — | — |
| 331-245 | Hanover Park | Cook | T-Mobile Usa, Inc. | Wireless | 2013-04-18 |
| 331-246 | — | — | — | — | — |
| 331-247 | — | — | — | — | — |
| 331-248 | Geneva | Kane | Comcast Phone Of Illinois, Llc Dba Comco | Landline | 2007-07-06 |
| 331-249 | — | — | — | — | — |
| 331-250 | Aurora | Kane | T-Mobile Usa, Inc. | Wireless | 2012-04-10 |
| 331-251 | Downers Grove | Dupage | Cellco Partnership Dba Verizon Wireless | Wireless | 2012-12-05 |
| 331-252 | — | — | — | — | — |
| 331-253 | Homer Glen | Will | T-Mobile Usa, Inc. | Wireless | 2014-10-27 |
| 331-254 | Sugar Grove | Kane | T-Mobile Usa, Inc. | Wireless | 2014-07-16 |
| 331-255 | — | — | — | — | — |
| 331-256 | Aurora | Kane | Cellco Partnership Dba Verizon Wireless | Wireless | 2011-09-13 |
| 331-257 | — | — | — | — | — |
| 331-258 | — | — | — | — | — |
| 331-259 | — | — | — | — | — |
| 331-260 | — | — | — | — | — |
| 331-261 | — | — | — | — | — |
| 331-262 | Aurora | Kane | Sprint Spectrum L.p. | Wireless | 2008-07-30 |
| 331-263 | — | — | — | — | — |
| 331-264 | — | — | — | — | — |
| 331-265 | — | — | — | — | — |
| 331-266 | — | — | — | — | — |
| 331-267 | — | — | — | — | — |
| 331-268 | — | — | — | — | — |
| 331-269 | — | — | — | — | — |
| 331-270 | — | — | — | — | — |
| 331-271 | — | — | — | — | — |
| 331-272 | — | — | — | — | — |
| 331-273 | — | — | — | — | — |
| 331-274 | — | — | — | — | — |
| 331-275 | — | — | — | — | — |
| 331-276 | Geneva | Kane | Cellco Partnership Dba Verizon Wireless | Wireless | 2014-11-10 |
| 331-277 | — | — | — | — | — |
| 331-278 | — | — | — | — | — |
| 331-279 | — | — | — | — | — |
| 331-280 | — | — | — | — | — |
| 331-281 | Naperville | Dupage | Ameritech Illinois | Landline | 2012-10-25 |
| 331-282 | — | — | — | — | — |
| 331-283 | — | — | — | — | — |
| 331-284 | — | — | — | — | — |
| 331-285 | — | — | — | — | — |
| 331-286 | — | — | — | — | — |
| 331-287 | — | — | — | — | — |
| 331-288 | — | — | — | — | — |
| 331-289 | — | — | — | — | — |
| 331-290 | — | — | — | — | — |
| 331-291 | — | — | — | — | — |
| 331-292 | — | — | — | — | — |
| 331-293 | — | — | — | — | — |
| 331-294 | — | — | — | — | — |
| 331-295 | — | — | — | — | — |
| 331-296 | — | — | — | — | — |
| 331-297 | — | — | — | — | — |
| 331-298 | — | — | — | — | — |
| 331-299 | — | — | — | — | — |
| 331-300 | — | — | — | — | — |
| 331-301 | Aurora | Kane | Local Access Llc | Landline | 2013-03-13 |
| 331-302 | Aurora | Kane | Cellco Partnership Dba Verizon Wireless | Wireless | 2013-02-11 |
| 331-303 | Elburn | Kane | Cibolo Creek Ventures, Llc Dba Routepoint Comm Il | Landline | 2013-04-22 |
| 331-304 | Hanover Park | Cook | T-Mobile Usa, Inc. | Wireless | 2015-02-20 |
| 331-305 | Naperville | Dupage | Cellco Partnership Dba Verizon Wireless | Wireless | 2013-08-15 |
| 331-306 | — | — | — | — | — |
| 331-307 | Lombard | Dupage | T-Mobile Usa, Inc. | Wireless | 2014-10-13 |
| 331-308 | Hanover Park | Cook | Bandwidth.com Clec, Llc | Landline | 2014-12-23 |
| 331-309 | — | — | — | — | — |
| 331-310 | Big Rock | Kane | Bandwidth.com Clec, Llc | Landline | 2014-12-29 |
| 331-311 | — | — | — | — | — |
| 331-312 | — | — | — | — | — |
| 331-313 | — | — | — | — | — |
| 331-314 | — | — | — | — | — |
| 331-315 | — | — | — | — | — |
| 331-316 | — | — | — | — | — |
| 331-317 | — | — | — | — | — |
| 331-318 | Homer Glen | Will | Local Access Llc | Landline | 2013-08-01 |
| 331-319 | — | — | — | — | — |
| 331-320 | — | — | — | — | — |
| 331-321 | Dupage | Dupage | T-Mobile Usa, Inc. | — | 2015-07-20 |
| 331-322 | — | — | — | — | — |
| 331-323 | — | — | — | — | — |
| 331-324 | — | — | — | — | — |
| 331-325 | — | — | — | — | — |
| 331-326 | — | — | — | — | — |
| 331-327 | — | — | — | — | — |
| 331-328 | — | — | — | — | — |
| 331-329 | — | — | — | — | — |
| 331-330 | Montgomery | Kendall | New Cingular Wireless Pcs, Llc | Landline | 2008-08-19 |
| 331-331 | — | — | — | — | — |
| 331-332 | Naperville | Dupage | New Cingular Wireless Pcs, Llc | Wireless | 2008-11-03 |
| 331-333 | Naperville | Dupage | New Cingular Wireless Pcs, Llc | Wireless | 2008-11-03 |
| 331-334 | — | — | — | — | — |
| 331-335 | — | — | — | — | — |
| 331-336 | — | — | — | — | — |
| 331-337 | — | — | — | — | — |
| 331-338 | — | — | — | — | — |
| 331-339 | — | — | — | — | — |
| 331-340 | — | — | — | — | — |
| 331-341 | — | — | — | — | — |
| 331-342 | — | — | — | — | — |
| 331-343 | — | — | — | — | — |
| 331-344 | — | — | — | — | — |
| 331-345 | — | — | — | — | — |
| 331-346 | — | — | — | — | — |
| 331-347 | — | — | — | — | — |
| 331-348 | — | — | — | — | — |
| 331-349 | — | — | — | — | — |
| 331-350 | — | — | — | — | — |
| 331-351 | — | — | — | — | — |
| 331-352 | — | — | — | — | — |
| 331-353 | — | — | — | — | — |
| 331-354 | — | — | — | — | — |
| 331-355 | — | — | — | — | — |
| 331-356 | — | — | — | — | — |
| 331-357 | — | — | — | — | — |
| 331-358 | — | — | — | — | — |
| 331-359 | — | — | — | — | — |
| 331-360 | — | — | — | — | — |
| 331-361 | — | — | — | — | — |
| 331-362 | — | — | — | — | — |
| 331-363 | — | — | — | — | — |
| 331-364 | — | — | — | — | — |
| 331-365 | — | — | — | — | — |
| 331-366 | — | — | — | — | — |
| 331-367 | — | — | — | — | — |
| 331-368 | — | — | — | — | — |
| 331-369 | — | — | — | — | — |
| 331-370 | — | — | — | — | — |
| 331-371 | — | — | — | — | — |
| 331-372 | — | — | — | — | — |
| 331-373 | — | — | — | — | — |
| 331-374 | — | — | — | — | — |
| 331-375 | — | — | — | — | — |
| 331-376 | — | — | — | — | — |
| 331-377 | — | — | — | — | — |
| 331-378 | — | — | — | — | — |
| 331-379 | — | — | — | — | — |
| 331-380 | — | — | — | — | — |
| 331-381 | — | — | — | — | — |
| 331-382 | — | — | — | — | — |
| 331-383 | — | — | — | — | — |
| 331-384 | — | — | — | — | — |
| 331-385 | — | — | — | — | — |
| 331-386 | — | — | — | — | — |
| 331-387 | — | — | — | — | — |
| 331-388 | — | — | — | — | — |
| 331-389 | — | — | — | — | — |
| 331-390 | — | — | — | — | — |
| 331-391 | — | — | — | — | — |
| 331-392 | — | — | — | — | — |
| 331-393 | — | — | — | — | — |
| 331-394 | — | — | — | — | — |
| 331-395 | — | — | — | — | — |
| 331-396 | — | — | — | — | — |
| 331-397 | — | — | — | — | — |
| 331-398 | — | — | — | — | — |
| 331-399 | — | — | — | — | — |
Area code 331 serves Illinois, including Aurora. It covers 22 cities across 5 counties, in the Central time zone.
Area code 331 observes Central time (UTC-06:00). The current local time is approximately 2:41 PM.
The earliest phone prefix recorded in area code 331 was put in service on 2007-07-06. The most recent was activated on 2015-09-16.
Our directory holds 407 caller reports covering 141 numbers in area code 331. A valid area code does not guarantee a legitimate caller, since numbers can be spoofed.
The largest places served by area code 331 are Aurora, Naperville, Geneva, Downers Grove, Elmhurst, Hanover Park, Homer Glen, Lombard. In total it covers 22 cities across 5 counties.
A number in this area code is written +1 (331) XXX-XXXX in international format, or (331) XXX-XXXX domestically. The +1 is the country code shared by the United States, Canada and other NANP members.
Yes. Caller ID was built without verification, so a caller can display almost any number. Scammers often pick a number matching the area code of the person they are calling — known as neighbour spoofing — because a local-looking call is answered more often. The US industry response, STIR/SHAKEN, lets carriers sign and verify caller ID, but coverage is still incomplete.
Almost always neighbour spoofing: the caller fabricates a number sharing your area code, and sometimes your prefix, so the call looks like it comes from someone nearby. A matching area code is not evidence that the caller is local.
Report unwanted calls to the FTC at reportfraud.ftc.gov, and add your number to the Do Not Call registry at donotcall.gov. Include the caller ID number even if you believe it was spoofed — regulators use the pattern of reports, not the individual number.
Different parts of this page carry different levels of reliability. Here is what each one rests on.
About the caller reports: these were submitted by members of the public and are not verified. They record what a caller ID displayed and what the recipient made of the call — they are not proof of who owns a number, and because caller ID can be faked, a reported number may have nothing to do with the person actually calling.
Search our directory of US listings by number, name or city.