| Abbreviation | Definition |
|---|---|
| NTS | NetWare Telephony Services |
| NTS | Network Telephony Services |
| NTS | Networking and Telecommunications Services |
| NTS | Number Translation Service |
| NTTA | National Tribal Telecommunications Association |
| NTTC | National Telco Television Consortium |
| NTTN | Nationwide Telecommunication Transmission Network |
| NTTN | Nationwide Telecommunications Transmission Network |
| NUTE | National Union of Telecommunications Employees |
| NVQ | Normal Voice Quality |
| NWD | Nation-Wide Dialing |
| NWH | National Wireless Holdings |
| NWI | Novatel Wireless, Inc. |
| NWN | No Wires Needed |
| NxTT | National xDSL Test Tool |
| NXX | North American direct distance dialing numbering plan, 'n' Is Any Number From 2 To 9, and 'x' Is Any Number From 0 To 9 |
| NYIIX | New York International Internet Exchange |
| NYU | New York Ultranet |
| O | Operator |
| O2U | O2-Utilization |