| Communications Technology Investment Limited | Private company limited by shares | Live |
| MAPLE LEAF COMMUNICATIONS TECHNOLOGY LIMITED | Private company limited by shares | Dissolved |
| LEGEND COMMUNICATIONS TECHNOLOGY CO., LIMITED | Private company limited by shares | Live |
| New Legend Communications Technology Co., Limited | Private company limited by shares | Live |
| LINKING COMMUNICATIONS TECHNOLOGY LIMITED | Private company limited by shares | Live |
| MontCloud Communications Technology Co., Limited | | Live |
| NEOLINK COMMUNICATIONS TECHNOLOGY LIMITED | Private company limited by shares | Live |
| Wa Yin Network Technology Communications Limited | Private company limited by shares | Live |
| PACIFIC COMMUNICATIONS TECHNOLOGY LIMITED | Private company limited by shares | Dissolved |
| PHONELIN COMMUNICATIONS TECHNOLOGY (H.K.) CO., LIMITED | Private company limited by shares | Live |
| SPACE COMMUNICATIONS TECHNOLOGY LIMITED | Private company limited by shares | Live |
| TELNET COMMUNICATIONS TECHNOLOGY LIMITED | Private company limited by shares | Dissolved |
| WORLD-POINT COMMUNICATIONS TECHNOLOGY (HK) CO., LIMITED | Private company limited by shares | Live |
| X-LINK COMMUNICATIONS TECHNOLOGY (HK) CO., LIMITED | Private company limited by shares | Live |
| YILONG COMMUNICATIONS TECHNOLOGY (HK) LIMITED | Private company limited by shares | Dissolved |
| SHENZHEN ZHONGYITONG COMMUNICATIONS ELECTRONIC TECHNOLOGY LIMITED | Private company limited by shares | Live |
| TECHNOWLEDGE COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TECH-VISION COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| Tech-Vision Communications (Hong Kong) Limited | Private company limited by shares | Dissolved |
| TECHWIN COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TEENS COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TEEPLUS COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TELE-AGE COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TELE-AGE COMMUNICATIONS INTERNATIONAL LIMITED | Private company limited by shares | Dissolved |
| TELEMAX COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TELEMETRO COMMUNICATIONS (H.K.) LIMITED | Private company limited by shares | Live |
| ADVANCED TELEPHONE COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TELEPOWER COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TELEROUTE COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| Televoice Communications HK Limited | Private company limited by shares | Dissolved |
| TELEWAY COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TELE-WAY COMMUNICATIONS INTERNATIONAL CO. LIMITED | Private company limited by shares | Dissolved |
| TELEWAY COMMUNICATIONS INVESTMENT LIMITED | Private company limited by shares | Dissolved |
| TELEWIDE COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TELHOPE COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TELMAX COMMUNICATIONS CORPORATION (H.K.) LIMITED | Private company limited by shares | Dissolved |
| TELNEXT COMMUNICATIONS HK LIMITED | Private company limited by shares | Dissolved |
| Telox Communications Co., Limited | Private company limited by shares | Live |
| TELPO COMMUNICATIONS INVESTMENT LIMITED | Private company limited by shares | Dissolved |
| TELUS COMMUNICATIONS INC LIMITED | Private company limited by shares | Live |
| TEMPO COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| Tennda Communications Limited | | Live |
| TENRY COMMUNICATIONS CO., LIMITED | Private company limited by shares | Live |
| TERA COMMUNICATIONS, LIMITED | Private company limited by shares | Dissolved |
| TERICOM COMMUNICATIONS (HONG KONG) COMPANY LIMITED | Private company limited by shares | Dissolved |
| MORE THAN COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| THERMOR COMMUNICATIONS (HONG KONG) LIMITED | Private company limited by shares | Dissolved |
| THINKER COMMUNICATIONS TECHNOLOGY (HK) CO., LIMITED | Private company limited by shares | Dissolved |
| Thrive PR & Communications Limited | Private company limited by shares | Live |
| Tianfeng (Hong Kong) Communications Limited | Private company limited by shares | Live |
| TIANQIN COMMUNICATIONS (HK) LIMITED | Private company limited by shares | Dissolved |
| TianShiLi Communications equipment Limited | Private company limited by shares | Dissolved |
| TIANYU COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TIEN-DI COMMUNICATIONS COMPANY LIMITED | Private company limited by shares | Live |
| T.M. COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TOKEY COMMUNICATIONS SERVICE LIMITED | Private company limited by shares | Live |
| TOMORROW COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| HOT TONE COMMUNICATIONS INTERNATIONAL LIMITED | Private company limited by shares | Dissolved |
| LUCKY TONE COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| Tongzhou Communications Limited | Private company limited by shares | Live |
| TONNET COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TOOB Creative Communications Limited | Private company limited by shares | Live |
| TOPLIST COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TOPS COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TOPWISE COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| Toro Communications Limited | Private company limited by shares | Live |
| TOTAL COMMUNICATIONS CORPORATION LIMITED | Private company limited by shares | Dissolved |
| TOWER COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| T.P. COMMUNICATIONS COMPANY LIMITED | Private company limited by shares | Live |
| FACEFONE TRADING AND COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| HANDART COMMUNICATIONS TRADING LIMITED | Private company limited by shares | Dissolved |
| COMMUNICATIONS TRADING (HK) LIMITED | Private company limited by shares | Live |
| COMMUNICATIONS HUB TRADING (HK) LIMITED | Private company limited by shares | Live |
| MORGENSTERN TRADING & COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| Telcel Communications and Trading Limited | Private company limited by shares | Dissolved |
| TELPO COMMUNICATIONS TRADING COMPANY LIMITED | Private company limited by shares | Dissolved |
| VTech Communications Trading Limited | Private company limited by shares | Live |
| TRANS COM COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TRANS COMMUNICATIONS LIMITED | | Live |
| TRANSGLOBAL COMMUNICATIONS GROUP HK LIMITED | Private company limited by shares | Dissolved |
| TRANSLINK COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TRANSMEDIA COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TRANS-NOVA COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TRANS-PACIFIC COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| AERO-SPACE TRAVEL SATELLITE COMMUNICATIONS (HK) COMPANY LIMITED | Private company limited by shares | Dissolved |
| SPACE TRAVEL COMMUNICATIONS LIMITED | | Live |
| Oak Tree Communications Limited | Private company limited by shares | Live |
| TRILOGY COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| Triniti Communications Limited | Private company limited by shares | Live |
| TRINITY COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TRIO COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TRIO Communications Limited | Private company limited by shares | Live |
| TRIPLEX COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TRIPOD COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TROIKA COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TROON COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TRUE COMMUNICATIONS LIMITED | Private company limited by shares | Live |
| TruLink Communications Limited | Private company limited by shares | Live |
| TUMBLEWEED COMMUNICATIONS LIMITED | Private company limited by shares | Dissolved |
| TUNG NAM COMMUNICATIONS LIMITED | Private company limited by shares | Live |