Phone numbers in Waterbury, Connecticut
Waterbury has 70 phone prefixes in area codes 203, 475.
Biggest holders: AT&T (local phone), AT&T Mobility, Verizon Wireless. This is the local calling area (rate center) where those prefixes were first assigned.
- Mobile carrier 50%
- Local phone company 33%
- Internet / business phone carrier 17%
Every prefix in Waterbury
Search the first six digits of a number in this list. If it's here, the number started in Waterbury with the carrier shown. If it isn't, check the Connecticut page or look the number up.
| Prefix | Carrier | Type | Assigned |
|---|---|---|---|
| 203-206 | AT&T Mobility | Mobile carrier | – |
| 203-217 | AT&T Mobility | Mobile carrier | – |
| 203-228 | Verizon Wireless | Mobile carrier | 2002 |
| 203-232 | Verizon Wireless | Mobile carrier | – |
| 203-233 | Verizon Wireless | Mobile carrier | – |
| 203-236 | AT&T (local phone) | Local phone company | – |
| 203-346 | AT&T (local phone) | Local phone company | – |
| 203-419 | AT&T (local phone) | Local phone company | – |
| 203-437 | MCImetro (Verizon Business) | Internet / business phone carrier | – |
| 203-465 | AT&T (local phone) | Local phone company | – |
| 203-509 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 203-510 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 203-518 | AT&T Mobility | Mobile carrier | 2001 |
| 203-519 | MetroPCS (T-Mobile) | Mobile carrier | 2011 |
| 203-525 | AT&T Mobility | Mobile carrier | – |
| 203-527 | AT&T (local phone) | Local phone company | – |
| 203-528 | Level 3 (Lumen) | Internet / business phone carrier | – |
| 203-558 | AT&T Mobility | Mobile carrier | – |
| 203-560 | AT&T Mobility | Mobile carrier | – |
| 203-565 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 203-568 | Windstream (PAETEC) | Internet / business phone carrier | – |
| 203-573 | AT&T (local phone) | Local phone company | – |
| 203-574 | AT&T (local phone) | Local phone company | – |
| 203-575 | AT&T (local phone) | Local phone company | – |
| 203-577 | AT&T (local phone) | Local phone company | – |
| 203-578 | AT&T (local phone) | Local phone company | – |
| 203-591 | AT&T (local phone) | Local phone company | – |
| 203-592 | AT&T Mobility | Mobile carrier | – |
| 203-596 | AT&T (local phone) | Local phone company | – |
| 203-597 | AT&T (local phone) | Local phone company | – |
| 203-598 | AT&T (local phone) | Local phone company | – |
| 203-695 | AT&T (local phone) | Local phone company | – |
| 203-706 | Windstream (PAETEC) | Internet / business phone carrier | 2004 |
| 203-707 | Verizon Wireless | Mobile carrier | 2011 |
| 203-709 | AT&T (local phone) | Local phone company | – |
| 203-721 | Verizon Wireless | Mobile carrier | – |
| 203-725 | Comcast | Internet / business phone carrier | – |
| 203-753 | AT&T (local phone) | Local phone company | – |
| 203-754 | AT&T (local phone) | Local phone company | – |
| 203-755 | AT&T (local phone) | Local phone company | – |
| 203-756 | AT&T (local phone) | Local phone company | – |
| 203-757 | AT&T (local phone) | Local phone company | – |
| 203-758 | AT&T (local phone) | Local phone company | – |
| 203-759 | AT&T (local phone) | Local phone company | – |
| 203-768 | T-Mobile (including Sprint) | Mobile carrier | – |
| 203-802 | MetroPCS (T-Mobile) | Mobile carrier | 2008 |
| 203-805 | Teleport Communications America | Internet / business phone carrier | – |
| 203-808 | T-Mobile (including Sprint) | Mobile carrier | 2002 |
| 203-819 | AT&T Mobility | Mobile carrier | – |
| 203-841 | Windstream (PAETEC) | Internet / business phone carrier | – |
| 203-910 | Verizon Wireless | Mobile carrier | – |
| 203-982 | MetroPCS (T-Mobile) | Mobile carrier | – |
| 475-222 | Peerless Network Of Connecticut | Internet / business phone carrier | 2012 |
| 475-233 | AT&T Mobility | Mobile carrier | 2016 |
| 475-235 | AT&T Mobility | Mobile carrier | 2011 |
| 475-263 | Peerless Network Of Connecticut | Internet / business phone carrier | 2019 |
| 475-295 | AT&T Mobility | Mobile carrier | 2021 |
| 475-305 | T-Mobile (including Sprint) | Mobile carrier | 2021 |
| 475-313 | T-Mobile (including Sprint) | Mobile carrier | 2015 |
| 475-316 | T-Mobile (including Sprint) | Mobile carrier | 2022 |
| 475-326 | T-Mobile (including Sprint) | Mobile carrier | 2023 |
| 475-337 | T-Mobile (including Sprint) | Mobile carrier | 2022 |
| 475-341 | T-Mobile (including Sprint) | Mobile carrier | 2023 |
| 475-354 | Onvoy | Internet / business phone carrier | 2024 |
| 475-377 | Fractel | Internet / business phone carrier | 2020 |
| 475-389 | AT&T Mobility | Mobile carrier | 2025 |
| 475-403 | Onvoy | Internet / business phone carrier | 2026 |
| 475-557 | Verizon Wireless | Mobile carrier | 2018 |
| 475-559 | Verizon Wireless | Mobile carrier | 2015 |
| 475-689 | Verizon Wireless | Mobile carrier | 2014 |
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.