| CoID | Company | Type | Status | States Served | 24X7 Phone |
| ACAT | Aventure Communication & Technology - CANCELLED | CLEC Facility | VoIP | C | IA | NE | SD | 712-255-3085 |
| ACC | Akron Canton Communications (Cancelled) | Reseller | C | OH | 330-699-5699 |
| ACC14 | America's Call Center | PBX/PS911/Shared Tenant | A | USA - Nationwide | 904-224-2000 |
| ACC21 | ACC Telecom | VoIP Reseller | A | USA - Nationwide | 910-471-3057 |
| ACCB | Arrowhead Communications Corp. | LEC | A | US | 800-992-8857 |
| ACCES | Accessible Wireless (CANCELLED) | Wireless | C | CA, AZ | 949-439-2888 |
| ACCIP | Accipiter Communications Inc. | ILEC | A | AZ | 623-455-4500 |
| ACCNT | ACCENT COMMUNICATION SERVICES INC | VoIP Provider | A | USA - Nationwide | 740-548-7378 |
| ACDC | Adept Communication and Data Company Inc | VoIP Reseller VoIP Provider | A | USA - Nationwide | 240-674-9422 |
| ACDEL | ACD Telecom | Facility | A | MI | 517-999-9999 |
| ACE | ACE Hardware Corporation | PBX/PS911/Shared Tenant | A | IL | 815-872-3000 |
| ACECM | Ace Telephone Association dba AcenTek | ILEC | A | MN | IA | 507-896-3192 |
| ACEIN | ACE Innovative Networks | VoIP Provider | A | USA | 212-931-9034 |
| ACELK | Ace Link Telecommunciations Inc dba AcenTek | CLEC Facility | A | MN | 507-896-3192 |
| ACEMI | Ace Telephone Company of MI Inc | ILEC | A | MI | 507-896-3107 |
| ACG | Advanced Communicatons Group (Out of Business) | CLEC | C | TX, KS, MO, OK | 877-333-2555 |
| ACG01 | Arlington County | PBX/PS911/Shared Tenant | A | VA | 703-558-2222 |
| ACG20 | Agility Communications Group | PBX/PS911/Shared Tenant VoIP Reseller VoIP Provider | A | USA - Nationwide | 972-715-8900 Option 2 |
| ACI | ALLTEL Communications, Inc. (Cancelled - see WINC) | Facility | C | ALL | 800-392-0186 |
| ACINC | AudioCodes Inc | VoIP Reseller | A | USA - Nationwide | 800-735-4588 |
| ACIW | Alltel Communications Inc. - CANCELLED | Wireless/Cellular/PCS | C | ALL | 501-607-4594 |
| ACME | Acme Communications Inc. | CLEC Facility | A | IN | 219-879-6600 |
| ACN61 | Arrival Communications (CANCELLED) | CLEC Facility | C | CA | 800-851-6705 |
| ACNDP | All Communication Services LLC | VoIP Provider | A | USA - Nationwide | 866-662-6645 |
| ACOLL | Austin College(Cancelled) | CLEC Facility, ILEC, VoIP | C | TX | 903-813-2555 |
| ACOM | ACOM LLC | VoIP Provider | A | VA | 540-631-5460 |
| ACOMM | Access Communications, LLC (INACTIVE) | CLEC Reseller, CLEC UNE | C | FL | 904-463-6500 |
| ACONA | Accoona Global LLC | VoIP Reseller VoIP Provider | A | USA - Nation Wide | 682-400-4800 |
| ACPNY | AdvantageCare Physicians | PBX/PS911/Shared Tenant | A | NY | 646-680-1302 |
| ACPS | Appomattox County Public Schools | VoIP Provider | A | VA | 434-664-8984 |
| ACS | Arvig Communication Systems, Inc. (INACTIVE) | LEC, CLEC | C | MN | 218-346-5500 |
| ACSAK | Alaska Communications Systems - CANCELLED | ILEC VoIP Provider | C | AK | 907-564-1642 |
| ACSI | Xspedius Management Company (CANCELLED) | Facility | C | AL, AR, AZ, CO, DC, FL, GA, KS, KY, LA, MD, MO, MS, NC, NM, | 800-937-7473 |
| ACT | Advanced Communications Technology Inc. | CLEC Facility CLEC Reseller CLEC UNE Co-Op/Rural ILEC VoIP Reseller VoIP Provider | A | WY | 307-673-0910 |
| ACTCI | Absaraka Cooperative Telephone Co. Inc. - CANCELLED | ILEC | C | ND | 701-896-3404 |
| ACTCO | Action Communications Inc. | Facility | A | NE | 308-632-7836 |
| ACTEL | Actel Integrated Communications, Inc. (Cancelled) | ICP | C | ALL | 877-700-9400 |
| ACTMA | Town of Acton - CANCELLED | 9-1-1 Admin-CPE ALI (9-1-1 Jurisdiction/PSAP ONLY) | C | MA | 978-929-7711 |
| ACWAK | Alaska Communications Systems - CANCELLED | Wireless/Cellular/PCS | C | AK | 907-564-1642 |
| ADAMS | Adams Telephone Co-operative | Co-Op/Rural ILEC | A | IL | 217-696-4411 |
| ADAPT | Adaptium Technology | Other - (must identify below) | hosted pbx only | A | USA - Nation Wide | 858-206-9111 |
| ADB10 | Elevation Education Solutions LLC | 9-1-1 Admin-CPE ALI (9-1-1 Jurisdiction/PSAP ONLY) PBX/PS911/Shared Tenant VoIP Reseller | | USA - Nationwide | 714-470-8766 |
| ADH17 | New Test | 9-1-1 Admin-CPE ALI (9-1-1 Jurisdiction/PSAP ONLY) | | USA - Nationwide | 2026185997 |
| ADI | Analog Devices (INACTIVE) | PBX | C | Two buildings in Wilmington | 781-937-2880 |
| ADREM | Adrem Technologies | 9-1-1 Admin-CPE ALI (9-1-1 Jurisdiction/PSAP ONLY) VoIP Reseller VoIP Provider | A | USA - Nation Wide | 801-889-2304 |
| ADS | Atlantic Digestive Specialists PLLC | PBX/PS911/Shared Tenant | A | NH | 603-692-2228 |
| ADSC | Airbus DS Communications Inc. | 9-1-1 Admin-CPE ALI (9-1-1 Jurisdiction/PSAP ONLY) | A | FL | MD | NC | PA | TX | VA | 844-291-6988 |
| ADTI | Advanza Telecom Inc. - CANCELLED | CLEC UNE | VOiP | C | NJ | 888-423-8269 |
| ADV | Advanced Communications LLC | VoIP Provider | A | USA - Nationwide | 844-418-8647 |
| ADVG | Advantage Cellular Systems - CANCELLED | Carrier | C | TN | 615-464-2355 |