| CoID | Company | Type | Status | States Served | 24X7 Phone |
| ATU | ATU Telecommunications (Out of Business) | Facility | C | Anchorage, Byrd, Indian, Girdwood, Portage, Hope, AK | 907-564-1642 |
| ATUED | Arkansas Tech University | PBX/PS911/Shared Tenant | A | AR | 479-968-0646 |
| ATZ | ATX Telecommunications Services (Cancelled) | Reseller | C | PA, NJ, DE | 610-668-3000 |
| AUBN | Knology Inc. | CLEC Facility | A | | 877-566-5649 |
| AUD | Audian Inc. | VoIP Reseller VoIP Provider | A | USA - Nation Wide | 844-611-6110 |
| AUSER | Anyuser, Inc. (CANCELLED) | VoIP | C | CA | 858-831-0500 |
| AUSW | CSC WIRELESS LLC dba. ALTICE MOBILE | Wireless/Cellular/PCS | A | USA - Nationwide | 866-232-5455 |
| AVADV | AVAD Technologies | VoIP Reseller | A | USA - Nationwide | 800-733-4165 |
| AVAYA | Avaya | VoIP Provider | A | USA - Nationwide | 866-462-8292 |
| AVDNE | Advanced VoIP Data | VoIP Provider | A | USA - Nationwide | 248-313-2300 |
| AVF | Avfuel Corporation | SIP softphones via 3CX system | A | USA - Nationwide | 313-789-1291 |
| AVH | Androscoggin Valley Hospital | PBX/PS911/Shared Tenant | A | NH | 603-723-9605 |
| AVILA | AVILA (CANCELLED) | PBX/Facilt | C | NY | 800-829-0420 |
| AVOIP | AT&T | CLEC Facility VoIP Provider | A | USA - Nationwide | 888-249-4980 |
| AVR | Avaria - CANCELLED | VoIP Reseller | C | USA - Nationwide | 919-559-9693 |
| AVTS | Aviation Technical Services dialtone by Verizon - CANCELLED | PBX/PS911/Shared Tenant | C | WA | 425-423-3444 |
| AWC | All West Communications | Facility | A | UT | WY | 435-783-4361 |
| AWCC | Allied Wireless Communications Corp - CANCELLED | Wireless/Cellular/PCS | C | USA | 720-733-5360 NOC |
| AWE | Awesome Communications, Inc. (CANCELLED) | Reseller | C | GA, SC, LA | 877-231-2881 |
| AWX | Altaworx | VoIP Provider | A | USA - Nationwide | 404-902-5668 |
| AX911 | AccessCom - CANCELLED | CLEC Facility | CLEC UNE | C | Lafayette | LA | 877-204-6024 |
| AXIAT | Axia Technology Partners - CANCELLED | VoIP Reseller | C | USA Nation Wide | 317-489-5544 |
| AXO | AXO Communications LLC - CANCELLED | CLEC Facility | C | KY | NY | WV | 518-320-8720 |
| AXTL | ApexxTek | VoIP Reseller VoIP Provider | A | LA | 504-355-1601 |
| AXX91 | Axxess Networks LLC | VoIP Provider | A | USA - Nationwide | 610-833-9000 |
| AXXES | Axxess Healthcare Consult - CANCELLED | PBX/PS911/Shared Tenant | C | USA - Nation Wide | 2145757711 |
| AXXS | Blue Mountain Networks | CLEC Facility CLEC Reseller VoIP Provider | A | WA | 503-891-7578 |
| AYB | Al-Call Inc. | Facility | A | GA | 912-632-5911 |
| AZSOA | Lumen/State of Arizona | 9-1-1 Admin-CPE ALI (9-1-1 Jurisdiction/PSAP ONLY) PBX/PS911/Shared Tenant | A | AZ | 855-799-8898 opt 3 |
| AZTH | Aztech Communications - CANCELLED | CLEC Facility | C | AZ | 928-542-0568 |
| AZUSA | City of Azusa | PBX/PS911/Shared Tenant | A | USA - Nationwide | 626-244-8046 |
| BA812 | Brewster Academy | PBX/PS911/Shared Tenant | A | NH | 603-998-6952 |
| BAA1 | Barr Tell USA Inc. | CLEC Facility | VoIP Provider | A | USA | 917-549-0100 |
| BABO | Babson College | VoIP Provider | A | USA - Nationwide | 781-239-3999 |
| BAC1 | Bank of America/Merrill Lynch(Inactive) | ILEC | C | NY | 212-236-8992 |
| BACO | Baltimore County Government - CANCELLED | ILEC | VoIP Proivder | C | MD | 410-887-8200 |
| BACRI | Byrd Institute(Cancelled) | PBX/PS911/Shared Tenant | C | FL | 866-295-9696 |
| BADGE | CBS Telephone and Data | VoIP Provider | A | TX | 210-496-9800 |
| BAH01 | Booz Allen Hamilton - CANCELLED | PBX/PS911/Shared Tenant | C | USA - Nation Wide | 800-773-7911 |
| BAI | Bel Air Internet LLC | VoIP Reseller | A | CA | 818-449-2626 |
| BAKER | Baker and Mckenzie - CANCELLED | VoIP | C | DC | 703-967-4698 |
| BAM | Bell Atlantic Mobile (Cancelled) | Cellular | C | South Central & Western NC; Wetern half of SC; North East co | 908-306-7123 |
| BAND | Bandwidth | CLEC Facility Database Management System Provider Video Relay Service VoIP Provider VPC | A | USA - Nationwide | VI | PR | Guam | 855-864-7776 |
| BAND2 | Bandwidth | CLEC Facility Database Management System Provider Video Relay Service VoIP Provider VPC | A | USA - Nationwide | Virgin Islands | 866-864-7776 |
| BANDR | Bandwidth | CLEC Facility Database Management System Provider VoIP Provider VPC | A | USA - Nationwide | 866-864-7776 |
| BANTR | Banter Inc | 9-1-1 Admin-CPE ALI (9-1-1 Jurisdiction/PSAP ONLY) VoIP Reseller VoIP Provider | A | USA - Nationwide | 972-845-1500 |
| BARE | Bare Escentuals Inc. - CANCELLED | 9-1-1 Admin-CPE ALI (9-1-1 Jurisdiction/PSAP ONLY) | C | CA | 614-489-5778 |
| BARRY | Barry County Telephone Company - CANCELLED | ILEC | C | MI | 269-491-8700 |
| BART | S.F. Bay Area Rapid Transit - CANCELLED | Facility | C | CA | 888-611-0029 |
| BASC | Bascom Mutual Telephone Company | CLEC Facility | A | OH | 419-937-2222 |