| Business | Phone |
| Ties Technology 2269 1st Capitol Dr, St Charles 63301 | (636) 946-4923 |
| Precise Telecomm 2917 Orton St, St Charles 63301 | (636) 916-0586 |
| Micro Tele-Communications Inc 2360 Highway 94 South Outer Rd, St Charles 63303 | (636) 477-9976 |
| J & M Telecommunications 3800 Opal Dr, St Charles 63304 | (636) 939-0344 |