Phone numbers in Mt. Carroll, Illinois
Mt. Carroll has 3 phone prefixes in area codes 779, 815.
Biggest holders: AT&T Mobility, Brightspeed Of Illinois, Mediacom Telephony Of Illinois. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 33%
- Local phone company 33%
- Internet / business phone carrier 33%
Every prefix in Mt. Carroll
Search the first six digits of a number in this list. If it's here, the number started in Mt. Carroll with the carrier shown. If it isn't, check the Illinois page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 779-448 | AT&T Mobility | Mobile carrier | 2026 |
| 815-244 | Brightspeed Of Illinois | Local phone company | – |
| 815-906 | Mediacom Telephony Of Illinois | Internet / business phone carrier | 2006 |
Most prefixes are pooled: the 10,000 numbers in each are handed out in blocks of 1,000 to different carriers, and people can also take their numbers to another carrier. So the carrier shown is where the prefix started, not a guarantee about any one number. Source: NANPA central office code records, 2026-10-10.