| Business | Phone |
| Accutech Communications Inc 24 Thayer Rd, Waltham 2453 | (781) 736-0001 |
| Switch & Data Facilities Co 74 West St, Waltham 2451 | (781) 890-7760 |
| Bay State Telecom Sales & Svc 77 Rumford Ave, Waltham 2453 | (781) 899-1371 |
| Berkley Communication Svc Waltham 2453 | (781) 899-5800 |
| Net Insight 1050 Winter St # 1000, Waltham 2451 | (781) 890-0600 |
| Neutral Tandem Inc 42 Weston St, Waltham 2453 | (781) 647-7733 |
| Genesys Telecommunications 22 Stearns St, Waltham 2453 | (781) 736-0711 |
| Sbc Telecom 1050 Winter St, Waltham 2451 | (781) 530-3658 |
| Centrepath 265 Winter St, Waltham 2451 | (781) 902-5100 |
| Ctc Communications Corp 1432 Main St, Waltham 2451 | (781) 529-9500 |