779 Area Code in Illinois, United States

Description

Area code 779 is an overlay for area code 815, serving northern Illinois outside the Chicago metropolitan area. It was introduced in 2007 due to increasing demand for phone numbers in the region. The 779/815 area includes cities such as Rockford, Joliet, DeKalb, and Kankakee. It spans a mix of urban centers, suburban communities, and rural farmland, reflecting the diversity of northern Illinois. Ten-digit dialing is required throughout the area. While 815 holds historical significance, 779 is commonly used for newer mobile lines and businesses. The dual-code system ensures continuity while supporting regional growth and development.

Time & Time Zone

Time zone:

Central (GMT -06:00)

Current time:

Map

Major Cities

City	Prefixes
Rockford	(779) 200 , (779) 203 , (779) 207 , (779) 208 , (779) 210 , (779) 221 , (779) 300 , (779) 348 , (779) 368 , (779) 423 , (779) 500 , (779) 537 , (779) 696 , (779) 770 , (779) 771 , (779) 772 , (779) 774
Joliet	(779) 205 , (779) 206 , (779) 225 , (779) 233 , (779) 279 , (779) 379 , (779) 435 , (779) 456 , (779) 875
Dekalb	(779) 212 , (779) 222 , (779) 400 , (779) 777
Crystal Lake	(779) 220 , (779) 800 , (779) 994
Frankfort	(779) 216 , (779) 324 , (779) 333
Winnebago	(779) 256 , (779) 863
Wilmington	(779) 232 , (779) 429
La Salle	(779) 201 , (779) 223
Galena	(779) 202 , (779) 214
Marengo	(779) 548
Kankakee	(779) 236
Manteno	(779) 529

Counties

County	Prefixes
Winnebago	(779) 200 , (779) 203 , (779) 207 , (779) 208 , (779) 210 , (779) 221 , (779) 256 , (779) 300 , (779) 348 , (779) 368 , (779) 423 , (779) 475 , (779) 500 , (779) 537 , (779) 696 , (779) 770 , (779) 771 , (779) 772 , (779) 774 , (779) 863
Will	(779) 205 , (779) 206 , (779) 216 , (779) 225 , (779) 232 , (779) 233 , (779) 279 , (779) 324 , (779) 333 , (779) 379 , (779) 429 , (779) 435 , (779) 456 , (779) 875
Dekalb	(779) 209 , (779) 212 , (779) 222 , (779) 382 , (779) 400 , (779) 777
Mchenry	(779) 220 , (779) 444 , (779) 548 , (779) 800 , (779) 994
La Salle	(779) 201 , (779) 213 , (779) 215 , (779) 223
Kankakee	(779) 236 , (779) 529
Bureau	(779) 229 , (779) 432
Iroquois	(779) 218 , (779) 235
Ogle	(779) 226 , (779) 545
Jo Daviess	(779) 202 , (779) 214
Boone	(779) 552
Lee	(779) 861
Grundy	(779) 228
Whiteside	(779) 245
Kendall	(779) 999

Telephone Carriers

Carrier	Type	Prefixes (%)
Cellco Partnership Dba Verizon Wireless Il	Wireless	13%
Denali Spectrum License Llc	Wireless	9%
Peerless Network Of Illinois Llc Il	Landline	9%
Sprint Spectrum L P	Wireless	8%
Bandwidth Com Clec Llc Il	Landline	8%
Comcast Phone Of Illinois Llc Dba Comco Il	Landline	8%
Teleport Communications America Llc Il	Landline	6%
Cygnus Telecommunications Corporation Il	Landline	5%
Neutral Tandem Illinois Llc Il	Landline	3%
Sbc Internet Services Inc	Wireless	3%
Charter Fiberlink Illinois Llc Il	Landline	3%
Digital Network Access Communications Inc Il	Landline	2%
Ymax Communications Corp Il	Landline	2%
365 Wireless Llc	Wireless	2%
Ameritech Illinois	Landline	2%
T Mobile Usa Inc	Wireless	2%
Local Access Llc	Landline	2%
Broadvox Clec Llc Il	Landline	2%
Mcleodusa Telecommunications Services Inc Il	Landline	2%
Mediacom Telephony Of Illinois Llc Il	Landline	2%
New Cingular Wireless Pcs Llc Il	Wireless	2%
Iowa Wireless Services Lp	Wireless	2%
Tds Metrocom Inc Il	Landline	2%
Mtco Communications Inc	Landline	2%

Prefixes

Prefix	City	Carrier	Type
(779) 770	Rockford	Denali Spectrum License, Llc	Wireless
(779) 208	Rockford	Cellco Partnership Dba Verizon Wireless - Il	Wireless
(779) 235	Crescent City	Sbc Internet Services, Inc.	Wireless
(779) 994	Crystal Lake	Peerless Network of Illinois, Llc - Il	Landline
(779) 226	Polo	Comcast Phone of Illinois, Llc Dba Comco - Il	Landline
(779) 456	Joliet	T-mobile Usa, Inc.	Wireless
(779) 861	Dixon	Cellco Partnership Dba Verizon Wireless - Il	Wireless
(779) 206	Joliet	Cellco Partnership Dba Verizon Wireless - Il	Wireless
(779) 774	Rockford	Tds Metrocom Inc.-il	Landline
(779) 432	Sheffield	Mtco Communications, Inc.	Landline
(779) 548	Marengo	Bandwidth.com Clec, Llc - Il	Landline
(779) 324	Frankfort	Bandwidth.com Clec, Llc - Il	Landline
(779) 400	Dekalb	Ymax Communications Corp. - Il	Landline
(779) 205	Joliet	New Cingular Wireless Pcs, Llc - Il	Wireless
(779) 537	Rockford	Cellco Partnership Dba Verizon Wireless - Il	Wireless
(779) 545	Mount Morris	Comcast Phone of Illinois, Llc Dba Comco - Il	Landline
(779) 232	Wilmington	Teleport Communications America, Llc - Il	Landline
(779) 221	Rockford	Broadvox-clec, Llc - Il	Landline
(779) 444	Wonder Lake	Bandwidth.com Clec, Llc - Il	Landline
(779) 220	Crystal Lake	Bandwidth.com Clec, Llc - Il	Landline
(779) 201	La Salle	Cellco Partnership Dba Verizon Wireless - Il	Wireless
(779) 475	South Beloit	Charter Fiberlink - Illinois, Llc - Il	Landline
(779) 233	Joliet	Sprint Spectrum L.p.	Wireless
(779) 245	Sterling	Iowa Wireless Services, Lp	Wireless
(779) 202	Galena	Teleport Communications America, Llc - Il	Landline
(779) 218	Iroquois	Peerless Network of Illinois, Llc - Il
(779) 333	Frankfort	Neutral Tandem-illinois, Llc - Il	Landline
(779) 256	Winnebago
(779) 222	Dekalb	Cygnus Telecommunications Corporation - Il	Landline
(779) 368	Rockford	Comcast Phone of Illinois, Llc Dba Comco - Il	Landline
(779) 696	Rockford	Mcleodusa Telecommunications Services, Inc.- Il	Landline
(779) 429	Wilmington	Cygnus Telecommunications Corporation - Il	Landline
(779) 777	Dekalb	Denali Spectrum License, Llc	Wireless
(779) 300	Rockford	Sprint Spectrum L.p.	Wireless
(779) 500	Rockford	Teleport Communications America, Llc - Il	Landline
(779) 215	Tonica	Local Access Llc	Landline
(779) 529	Manteno	Bandwidth.com Clec, Llc - Il	Landline
(779) 225	Joliet	Cellco Partnership Dba Verizon Wireless - Il	Wireless
(779) 210	Rockford	Sbc Internet Services, Inc.	Landline
(779) 200	Rockford	Cellco Partnership Dba Verizon Wireless - Il	Wireless
(779) 382	Genoa	Charter Fiberlink - Illinois, Llc - Il	Landline
(779) 236	Kankakee	Sprint Spectrum L.p.	Wireless
(779) 213	Oglesby	Peerless Network of Illinois, Llc - Il	Landline
(779) 999	Newark	Cygnus Telecommunications Corporation - Il	Landline
(779) 207	Rockford	Cellco Partnership Dba Verizon Wireless - Il	Wireless
(779) 203	Rockford	Sprint Spectrum L.p.	Wireless
(779) 216	Frankfort	Peerless Network of Illinois, Llc - Il	Landline
(779) 212	Dekalb	365 Wireless, Llc	Wireless
(779) 552	Belvidere	Digital Network Access Communications, Inc. - Il	Landline
(779) 228	Mazon	Peerless Network of Illinois, Llc - Il	Landline
(779) 863	Winnebago
(779) 771	Rockford	Denali Spectrum License, Llc	Wireless
(779) 875	Joliet	Sprint Spectrum L.p.	Wireless
(779) 229	Bureau	Comcast Phone of Illinois, Llc Dba Comco - Il
(779) 423	Rockford	Comcast Phone of Illinois, Llc Dba Comco - Il	Landline
(779) 214	Galena	Mediacom Telephony of Illinois, Llc - Il	Landline
(779) 223	La Salle
(779) 379	Joliet	Denali Spectrum License, Llc	Wireless
(779) 348	Rockford	Teleport Communications America, Llc - Il	Landline
(779) 800	Crystal Lake	Neutral Tandem-illinois, Llc - Il	Landline
(779) 209	Sandwich	Peerless Network of Illinois, Llc - Il	Landline
(779) 279	Joliet	Denali Spectrum License, Llc	Wireless
(779) 435	Joliet	Ameritech Illinois	Landline
(779) 772	Rockford	Denali Spectrum License, Llc	Wireless