Phone numbers in Granite City, Illinois
Granite City has 25 phone prefixes in area codes 618, 730.
Biggest holders: AT&T (local phone), AT&T Mobility, T-Mobile (including Sprint). This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 44%
- Local phone company 36%
- Internet / business phone carrier 20%
Every prefix in Granite City
Search the first six digits of a number in this list. If it's here, the number started in Granite City with the carrier shown. If it isn't, check the Illinois page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 618-219 | Windstream (PAETEC) | Internet / business phone carrier | – |
| 618-225 | AT&T (local phone) | Local phone company | – |
| 618-373 | AT&T Mobility | Mobile carrier | 2020 |
| 618-419 | T-Mobile (including Sprint) | Mobile carrier | 2015 |
| 618-451 | AT&T (local phone) | Local phone company | – |
| 618-452 | AT&T (local phone) | Local phone company | – |
| 618-500 | Onvoy | Internet / business phone carrier | 2017 |
| 618-501 | Windstream (PAETEC) | Internet / business phone carrier | 2012 |
| 618-512 | AT&T (local phone) | Local phone company | – |
| 618-600 | Onvoy | Internet / business phone carrier | 2015 |
| 618-610 | AT&T Mobility | Mobile carrier | 2002 |
| 618-709 | T-Mobile (including Sprint) | Mobile carrier | 2001 |
| 618-794 | AT&T Mobility | Mobile carrier | 2021 |
| 618-797 | AT&T (local phone) | Local phone company | – |
| 618-798 | AT&T (local phone) | Local phone company | – |
| 618-801 | Onvoy | Internet / business phone carrier | 2016 |
| 618-802 | T-Mobile (including Sprint) | Mobile carrier | 2013 |
| 618-823 | T-Mobile (including Sprint) | Mobile carrier | 2009 |
| 618-876 | AT&T (local phone) | Local phone company | – |
| 618-877 | AT&T (local phone) | Local phone company | – |
| 618-931 | AT&T (local phone) | Local phone company | – |
| 618-981 | T-Mobile (including Sprint) | Mobile carrier | 2023 |
| 730-298 | AT&T Mobility | Mobile carrier | 2026 |
| 730-299 | AT&T Mobility | Mobile carrier | 2026 |
| 730-304 | AT&T Mobility | Mobile carrier | 2026 |
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.