Phone numbers in Norwalk, Connecticut
Norwalk has 82 phone prefixes in area codes 203, 475.
Biggest holders: AT&T (local phone), Verizon Wireless, T-Mobile (including Sprint). This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 43%
- Local phone company 27%
- Internet / business phone carrier 24%
- Paging service 5%
- Phone company 1%
Every prefix in Norwalk
Search the first six digits of a number in this list. If it's here, the number started in Norwalk with the carrier shown. If it isn't, check the Connecticut page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 203-229 | AT&T (local phone) | Local phone company | – |
| 203-246 | Verizon Wireless | Mobile carrier | – |
| 203-247 | Verizon Wireless | Mobile carrier | – |
| 203-286 | Windstream (PAETEC) | Internet / business phone carrier | – |
| 203-295 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 203-299 | AT&T (local phone) | Local phone company | – |
| 203-354 | Cablevision Lightpath | Internet / business phone carrier | – |
| 203-398 | Spok | Paging service | – |
| 203-434 | T-Mobile (including Sprint) | Mobile carrier | – |
| 203-505 | Verizon Wireless | Mobile carrier | – |
| 203-515 | T-Mobile (including Sprint) | Mobile carrier | – |
| 203-523 | Teleport Communications America | Internet / business phone carrier | – |
| 203-593 | Spok | Paging service | – |
| 203-604 | Level 3 (Lumen) | Internet / business phone carrier | 2001 |
| 203-613 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 203-642 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 203-644 | Verizon Wireless | Mobile carrier | – |
| 203-663 | Windstream (PAETEC) | Internet / business phone carrier | – |
| 203-722 | AT&T Mobility | Mobile carrier | – |
| 203-750 | AT&T (local phone) | Local phone company | – |
| 203-803 | Verizon Wireless | Mobile carrier | – |
| 203-807 | AT&T Mobility | Mobile carrier | 2001 |
| 203-810 | Cablevision Lightpath | Internet / business phone carrier | 2001 |
| 203-818 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 203-820 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 203-822 | AT&T (local phone) | Local phone company | – |
| 203-829 | T-Mobile (including Sprint) | Mobile carrier | – |
| 203-831 | AT&T (local phone) | Local phone company | – |
| 203-835 | Spok | Paging service | – |
| 203-838 | AT&T (local phone) | Local phone company | – |
| 203-839 | Spok | Paging service | – |
| 203-840 | AT&T (local phone) | Local phone company | – |
| 203-842 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 203-845 | AT&T (local phone) | Local phone company | – |
| 203-846 | AT&T (local phone) | Local phone company | – |
| 203-847 | AT&T (local phone) | Local phone company | – |
| 203-849 | AT&T (local phone) | Local phone company | – |
| 203-851 | AT&T (local phone) | Local phone company | – |
| 203-852 | AT&T (local phone) | Local phone company | – |
| 203-853 | AT&T (local phone) | Local phone company | – |
| 203-854 | AT&T (local phone) | Local phone company | – |
| 203-855 | AT&T (local phone) | Local phone company | – |
| 203-856 | Verizon Wireless | Mobile carrier | – |
| 203-857 | AT&T (local phone) | Local phone company | – |
| 203-858 | Verizon Wireless | Mobile carrier | – |
| 203-866 | AT&T (local phone) | Local phone company | – |
| 203-899 | AT&T (local phone) | Local phone company | – |
| 203-904 | T-Mobile (including Sprint) | Mobile carrier | – |
| 203-919 | T-Mobile (including Sprint) | Mobile carrier | – |
| 203-939 | Csc Voice | Internet / business phone carrier | 2008 |
| 203-943 | T-Mobile (including Sprint) | Mobile carrier | – |
| 203-945 | AT&T (local phone) | Local phone company | – |
| 203-952 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 203-956 | Cablevision Lightpath | Internet / business phone carrier | 2001 |
| 203-957 | Csc Voice | Internet / business phone carrier | 2011 |
| 203-963 | AT&T (local phone) | Local phone company | – |
| 203-970 | Cablevision Lightpath | Internet / business phone carrier | 2011 |
| 203-981 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 203-984 | Verizon Wireless | Mobile carrier | – |
| 203-991 | AT&T (local phone) | Local phone company | – |
| 475-208 | Level 3 (Lumen) | Internet / business phone carrier | 2014 |
| 475-245 | Verizon Wireless | Mobile carrier | 2016 |
| 475-250 | Verizon Wireless | Mobile carrier | 2018 |
| 475-257 | Csc Wireless | Mobile carrier | 2019 |
| 475-258 | T-Mobile (including Sprint) | Mobile carrier | 2019 |
| 475-266 | AT&T Mobility | Mobile carrier | 2015 |
| 475-283 | Verizon Wireless | Mobile carrier | 2016 |
| 475-288 | Level 3 (Lumen) | Internet / business phone carrier | 2014 |
| 475-291 | Verizon Wireless | Mobile carrier | 2021 |
| 475-322 | Verizon Wireless | Mobile carrier | 2016 |
| 475-393 | T-Mobile (including Sprint) | Mobile carrier | 2017 |
| 475-395 | Verizon Wireless | Mobile carrier | 2015 |
| 475-397 | Cablevision Lightpath | Internet / business phone carrier | 2025 |
| 475-459 | Verizon Wireless | Mobile carrier | 2018 |
| 475-470 | Onvoy | Internet / business phone carrier | 2016 |
| 475-489 | Verizon Wireless | Mobile carrier | 2015 |
| 475-544 | T-Mobile (including Sprint) | Mobile carrier | 2022 |
| 475-673 | TON80 Communications | Internet / business phone carrier | 2022 |
| 475-747 | Verizon Wireless | Mobile carrier | 2015 |
| 475-755 | Fractel | Internet / business phone carrier | 2020 |
| 475-850 | Barr Tel USA | Phone company | 2022 |
| 475-889 | Verizon Wireless | Mobile carrier | 2018 |
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.