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
La Salle	(779) 201 , (779) 223
Wilmington	(779) 232 , (779) 429
Winnebago	(779) 256 , (779) 863
Galena	(779) 202 , (779) 214
Mazon	(779) 228
Genoa	(779) 382
Sandwich	(779) 209

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
Jo Daviess	(779) 202 , (779) 214
Iroquois	(779) 218 , (779) 235
Kankakee	(779) 236 , (779) 529
Bureau	(779) 229 , (779) 432
Ogle	(779) 226 , (779) 545
Whiteside	(779) 245
Boone	(779) 552
Lee	(779) 861
Kendall	(779) 999
Grundy	(779) 228

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

Prefixes

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