Illinois

Area code 331

Area code 331 covers Aurora, Naperville, Downers Grove, St. Charles, Lombard and more in Illinois, in the Central time zone. It has been in service since 2007. It shares its area with 630 (an overlay).

WhereIllinois

Time zoneCentral

Exchanges225

Flagged numbers741 complaints

Most reported 331 numbers

(331) 888-1940Shady callDebt relief / loans14 complaintsBusiness loans (331) 888-1773Shady callRobocall / recorded message9 complaintsDebt relief / consolidation (331) 888-1662Shady callRobocall / recorded message5 complaintsBank / financial impersonation (331) 208-6201CautionRobocall / recorded message4 complaints (331) 279-9374CautionScam or spam text3 complaints (331) 223-4353CautionRobocall / recorded message3 complaints (331) 295-7764CautionPrize / sweepstakes3 complaintsPrizes / sweepstakes

Carriers in 331

Onvoy (Sinch)45 24%
T-Mobile42 22%
Verizon Wireless33 17%
AT&T Mobility26 14%
Fractel18 9%
Bandwidth11 6%
Ton80 Communications9 5%
Lumen (Level 3)6 3%

Line types

VoIP / internet phone115 51%
Wireless (cell phone)102 45%
Landline8 4%

Counted over the exchanges, from the carrier each was assigned to.

Cities in area code 331

AuroraNapervilleDowners GroveSt. CharlesLombardElmhurstLemontBartlett

Every 331 exchange

The first six digits of a number. Each one with 3 or more flagged numbers has its own page: who it was assigned to and the numbers in it.

Exchange	City	Carrier	Type	Flagged
331-200	Bartlett	T-Mobile	Wireless	0
331-201	Downers Grove	Verizon Wireless	Wireless	0
331-202	Elmhurst	T-Mobile	Wireless	0
331-203	Aurora	T-Mobile	Wireless	0
331-204	Naperville	Onvoy (Sinch)	VoIP	0
331-205	Aurora	T-Mobile	Wireless	0
331-206	Aurora	T-Mobile	Wireless	0
331-207	Yorkville	Lumen (Level 3)	VoIP	0
331-208	Aurora	Lumen (Level 3)	VoIP	1
331-209	Elmhurst	Lumen (Level 3)	VoIP	0
331-210	St. Charles	Peerless Network	VoIP	0
331-212	Aurora	Verizon Business	VoIP	0
331-213	Naperville	Verizon Wireless	Wireless	0
331-214	Downers Grove	Verizon Wireless	Wireless	0
331-215	Naperville	Verizon Wireless	Wireless	0
331-216	Oswego	AT&T Mobility	Wireless	0
331-217	Lombard	Onvoy (Sinch)	VoIP	0
331-218	Wheaton	T-Mobile	Wireless	0
331-219	Aurora	Telnyx	VoIP	0
331-220	Aurora	T-Mobile	Wireless	0
331-221	Elmhurst	AT&T	Landline	0
331-222	St. Charles	AT&T Mobility	Wireless	0
331-223	St. Charles	AT&T Mobility	Wireless	1
331-224	Itasca	Onvoy (Sinch)	VoIP	0
331-225	Elmhurst	T-Mobile	Wireless	0
331-226	Naperville	T-Mobile	Wireless	0
331-227	Sugar Grove	Verizon Wireless	Wireless	0
331-228	St. Charles	Windstream (PAETEC)	VoIP	0
331-229	Naperville	Verizon Wireless	Wireless	0
331-230	Aurora	T-Mobile	Wireless	0
331-231	Naperville	AT&T Mobility	Wireless	0
331-232	West Chicago	AT&T Mobility	Wireless	0
331-233	Downers Grove	Telnyx	VoIP	0
331-234	Sugar Grove	Verizon Wireless	Wireless	0
331-235	St. Charles	AT&T Mobility	Wireless	0
331-236	Wheaton	T-Mobile	Wireless	0
331-237	Naperville	Verizon Business	VoIP	0
331-238	Downers Grove	AT&T	VoIP	0
331-239	Yorkville	Onvoy (Sinch)	VoIP	0
331-240	West Chicago	Peerless Network	VoIP	0
331-241	Lombard	Onvoy (Sinch)	VoIP	0
331-242	Lombard	T-Mobile	Wireless	0
331-243	Lombard	T-Mobile	Wireless	0
331-244	Naperville	Onvoy (Sinch)	VoIP	0
331-245	Bartlett	T-Mobile	Wireless	0
331-246	Lemont	T-Mobile	Wireless	0
331-247	Naperville	Vonage	VoIP	0
331-248	Geneva	Comcast (Xfinity)	VoIP	0
331-249	Naperville	Onvoy (Sinch)	VoIP	0
331-250	Aurora	T-Mobile	Wireless	0
331-251	Downers Grove	Verizon Wireless	Wireless	0
331-252	Warrenville	AT&T	VoIP	0
331-253	Lemont	T-Mobile	Wireless	0
331-254	Sugar Grove	T-Mobile	Wireless	0
331-255	Aurora	Onvoy (Sinch)	VoIP	0
331-256	Aurora	Verizon Wireless	Wireless	0
331-257	Aurora	AT&T Mobility	Wireless	0
331-258	Aurora	Onvoy (Sinch)	VoIP	0
331-259	Sugar Grove	Peerless Network	VoIP	0
331-260	Downers Grove	AT&T	VoIP	0
331-261	Lemont	T-Mobile	Wireless	0
331-262	Aurora	T-Mobile	Wireless	0
331-263	Itasca	Onvoy (Sinch)	VoIP	0
331-264	Hinsdale	Lumen (Level 3)	VoIP	0
331-265	Geneva	Onvoy (Sinch)	VoIP	0
331-266	St. Charles	AT&T Mobility	Wireless	0
331-267	Lombard	Vonage	VoIP	0
331-268	Sugar Grove	T-Mobile	Wireless	0
331-269	Aurora	T-Mobile	Wireless	0
331-270	Aurora	Onvoy (Sinch)	VoIP	0
331-271	Hinsdale	Onvoy (Sinch)	VoIP	0
331-272	St. Charles	Onvoy (Sinch)	VoIP	0
331-273	Lemont	Onvoy (Sinch)	VoIP	0
331-274	Aurora	T-Mobile	Wireless	0
331-275	Bartlett	T-Mobile	Wireless	0
331-276	St. Charles	Verizon Wireless	Wireless	0
331-277	Lombard	AT&T Mobility	Wireless	0
331-278	Aurora	AT&T Mobility	Wireless	0
331-279	Elmhurst	Windstream (PAETEC)	VoIP	1
331-280	Downers Grove	Verizon Wireless	Wireless	0
331-281	Naperville	AT&T	Landline	0
331-282	Hinsdale	Onvoy (Sinch)	VoIP	0
331-283	Geneva	T-Mobile	Wireless	0
331-284	Bartlett	T-Mobile	Wireless	0
331-285	Naperville	Verizon Wireless	Wireless	0
331-286	St. Charles	Verizon Wireless	Wireless	0
331-287	Aurora	Bandwidth	VoIP	0
331-288	Elburn	Ton80 Communications	VoIP	0
331-289	Hinsdale	T-Mobile	Wireless	0
331-290	Aurora	Verizon Wireless	Wireless	0
331-291	Downers Grove	Verizon Wireless	Wireless	0
331-292	Downers Grove	Onvoy (Sinch)	VoIP	0
331-293	Aurora	AT&T Mobility	Wireless	0
331-294	Naperville	Verizon Wireless	Wireless	0
331-295	Aurora	Nuso	Landline	1
331-296	Wheaton	Boost Subscriberco	Landline	0
331-297	Batavia	Onvoy (Sinch)	VoIP	0
331-298	Naperville	Onvoy (Sinch)	VoIP	0
331-299	Hinsdale	Fractel	VoIP	0
331-300	Aurora	T-Mobile	Wireless	0
331-301	Aurora	T-Mobile (Metro)	Wireless	0
331-302	Aurora	Verizon Wireless	Wireless	0
331-303	Elburn	Bandwidth	VoIP	0
331-304	Bartlett	T-Mobile	Wireless	0
331-305	Naperville	Verizon Wireless	Wireless	0
331-306	Downers Grove	Onvoy (Sinch)	VoIP	0
331-307	Lombard	T-Mobile	Wireless	0
331-308	Bartlett	Bandwidth	VoIP	0
331-309	Lemont	Commio	VoIP	0
331-310	Big Rock	Bandwidth	VoIP	0
331-312	Aurora	Verizon Wireless	Wireless	0
331-313	Naperville	Onvoy (Sinch)	VoIP	0
331-314	St. Charles	Verizon Wireless	Wireless	0
331-315	Lombard	AT&T Mobility	Wireless	0
331-316	Naperville	Commio	VoIP	0
331-317	Hinsdale	Commio	VoIP	0
331-318	Lemont	Bandwidth	VoIP	0
331-319	Aurora	Onvoy (Sinch)	VoIP	0
331-320	Bartlett	Onvoy (Sinch)	VoIP	0
331-321	Aurora	T-Mobile	Wireless	0
331-322	Lombard	Onvoy (Sinch)	VoIP	0
331-323	Glen Ellyn	Onvoy (Sinch)	VoIP	0
331-324	Yorkville	Onvoy (Sinch)	VoIP	0
331-325	Lemont	Onvoy (Sinch)	VoIP	0
331-326	Downers Grove	Onvoy (Sinch)	VoIP	0
331-327	St. Charles	Verizon Wireless	Wireless	0
331-328	Naperville	AT&T Mobility	Wireless	0
331-329	Aurora	Onvoy (Sinch)	VoIP	0
331-330	Naperville	AT&T Mobility	Wireless	0
331-331	Aurora	Onvoy (Sinch)	VoIP	0
331-332	Naperville	AT&T Mobility	Wireless	0
331-333	Naperville	AT&T Mobility	Wireless	0
331-334	Batavia	Onvoy (Sinch)	VoIP	0
331-335	St. Charles	AT&T Mobility	Wireless	0
331-336	Aurora	Fractel	VoIP	0
331-337	Oswego	AT&T Mobility	Wireless	0
331-338	Aurora	Onvoy (Sinch)	VoIP	0
331-339	Aurora	Verizon Wireless	Wireless	0
331-340	Itasca	Onvoy (Sinch)	VoIP	0
331-341	Plano	Onvoy (Sinch)	VoIP	0
331-342	Naperville	Verizon Wireless	Wireless	0
331-343	Downers Grove	Onvoy (Sinch)	VoIP	0
331-344	West Chicago	Onvoy (Sinch)	VoIP	0
331-345	Naperville	Fractel	VoIP	0
331-346	Naperville	Verizon Wireless	Wireless	0
331-347	Wheaton	Onvoy (Sinch)	VoIP	0
331-348	Elburn	Fractel	VoIP	0
331-349	St. Charles	AT&T Mobility	Wireless	0
331-350	Hinsdale	Onvoy (Sinch)	VoIP	0
331-356	Bartlett	Fractel	VoIP	0
331-373	Oswego	Ton80 Communications	VoIP	0
331-385	Aurora	AT&T Mobility	Wireless	0
331-388	Sugar Grove	Fractel	VoIP	0
331-399	Downers Grove	Fractel	VoIP	0
331-400	Oswego	Fractel	VoIP	0
331-401	Naperville	Lumen (Level 3)	VoIP	0
331-422	St. Charles	Lumen (Level 3)	VoIP	0
331-425	Aurora	T-Mobile	Wireless	0
331-426	Lemont	Ton80 Communications	VoIP	0
331-431	Aurora	Bandwidth	VoIP	0
331-442	St. Charles	Verizon Wireless	Wireless	0
331-444	Naperville	Verizon Wireless	Wireless	0
331-452	Aurora	Verizon Wireless	Wireless	0
331-454	Aurora	AT&T Mobility	Wireless	0
331-456	Roselle	First Communications	Landline	0
331-457	Naperville	Verizon Wireless	Wireless	0
331-462	Lombard	Verizon Business	VoIP	0
331-465	West Chicago	AT&T Mobility	Wireless	0
331-466	Glen Ellyn	Ton80 Communications	VoIP	0
331-472	Naperville	T-Mobile	Wireless	0
331-481	Downers Grove	Verizon Wireless	Wireless	0
331-500	Geneva	Fractel	VoIP	0
331-529	Naperville	Fractel	VoIP	0
331-551	Lombard	AT&T Mobility	Wireless	0
331-575	Aurora	T-Mobile	Wireless	0
331-588	St. Charles	AT&T Mobility	Wireless	0
331-600	Wheaton	Fractel	VoIP	0
331-625	Downers Grove	Verizon Wireless	Wireless	0
331-627	Lombard	Ton80 Communications	VoIP	0
331-631	Downers Grove	Onvoy (Sinch)	VoIP	0
331-642	Elmhurst	Bandwidth	VoIP	0
331-643	Aurora	T-Mobile	Wireless	0
331-645	Elmhurst	T-Mobile	Wireless	0
331-666	Aurora	Onvoy (Sinch)	VoIP	0
331-684	Aurora	Rcn Telecom Services of Illinios	Landline	0
331-688	Naperville	Ton80 Communications	VoIP	0
331-701	Naperville	Verizon Wireless	Wireless	0
331-702	Naperville	Verizon Business	VoIP	0
331-703	West Chicago	T-Mobile	Wireless	0
331-704	Kaneville	Bandwidth	VoIP	0
331-707	Aurora	T-Mobile	Wireless	0
331-716	Wheaton	Onvoy (Sinch)	VoIP	0
331-717	Oswego	AT&T Mobility	Wireless	0
331-725	Oswego	AT&T Mobility	Wireless	0
331-732	Geneva	Fractel	VoIP	0
331-746	Kaneville	Ton80 Communications	VoIP	0
331-757	Lemont	T-Mobile	Wireless	0
331-758	Aurora	Fractel	VoIP	0
331-771	St. Charles	Onvoy (Sinch)	VoIP	0
331-775	Downers Grove	Comcast (Xfinity)	VoIP	0
331-777	Downers Grove	Verizon Wireless	Wireless	0
331-788	Geneva	Fractel	VoIP	0
331-800	West Chicago	Onvoy (Sinch)	VoIP	0
331-801	Downers Grove	AT&T	VoIP	0
331-803	Lemont	Peerless Network	VoIP	0
331-806	Wheaton	Comcast (Xfinity)	VoIP	0
331-808	Plano	Bandwidth	VoIP	0
331-814	Naperville	T-Mobile	Wireless	0
331-825	Geneva	Digital Network Access...	Landline	0
331-826	Elmhurst	T-Mobile	Wireless	0
331-837	West Chicago	Ton80 Communications	VoIP	0
331-850	Big Rock	Onvoy (Sinch)	VoIP	0
331-866	Wheaton	Ton80 Communications	VoIP	0
331-867	Yorkville	Fractel	VoIP	0
331-871	West Chicago	Onvoy (Sinch)	VoIP	0
331-888	Warrenville	Peerless Network	VoIP	3
331-899	Lombard	Fractel	VoIP	0
331-900	Elmhurst	Fractel	VoIP	0
331-901	St. Charles	Bandwidth	VoIP	0
331-903	Downers Grove	AT&T Enterprises	Landline	0
331-946	Glen Ellyn	Fractel	VoIP	0
331-979	Elmhurst	Comcast (Xfinity)	VoIP	0
331-980	Aurora	T-Mobile	Wireless	0
331-998	Downers Grove	Verizon Wireless	Wireless	0
331-999	Oswego	Bandwidth	VoIP	0

Area code 331 questions

Where is area code 331?

Area code 331 is in Illinois. Its biggest rate centers are Aurora, Naperville, Downers Grove, St. Charles, Lombard.

What time zone is area code 331?

Area code 331 is in the Central time zone.

Is a call from area code 331 a scam?

An area code alone can't tell you. Scammers use and spoof numbers in every area code. 7 331 numbers have been flagged on ShadyCall. Look up the full number to see its reports and FTC/FCC complaints.

What carriers use area code 331?

Of its 225 exchanges, the most were assigned to Onvoy (Sinch), T-Mobile, Verizon Wireless. Numbers can be ported to any carrier, so the exchange shows the original carrier only.

What area codes overlay 331?

331 shares its area with 630. In an overlay, new numbers get the newer codes and you dial all ten digits.