| Business | Phone |
| Access Technology Solutions 31 Church St, Markham L3P 2L7 | (905) 471-7100 |
| Skyway Telecommunications Syst 96 Main St N, Markham L3P 1X8 | (905) 471-1200 |
| Northern Media Solutions 7030 Woodbine Ave #500, Markham L3R 6G2 | (905) 943-4972 |
| Novx Microsystems Inc 2900 John St, Markham L3R 5G3 | (905) 474-5051 |
| Pacific Link Communications 570 Alden Rd, Markham L3R 8N5 | (905) 305-8100 |
| Pulse Software & Consulting 500 Alden Rd #216, Markham L3R 5H5 | (905) 415-0010 |
| Telnet Inc 2900 John St, Markham L3R 5G3 | (905) 477-0555 |
| Clear Channel 4300 Steeles Ave E, Markham L3R 0Y5 | (905) 415-5366 |
| Connect Telecom 62 Fairgate, Markham | (905) 642-4795 |
| Digicell.Net 4300 Steeles Ave E, Markham L3R 0Y5 | (905) 944-9959 |