(636) 534-6600

“Over 3,000 Businesses Have Trusted CSI Telecommunications, Inc. To Provide Cost Effective Communication Solutions In St. Louis Region For Over 45 Years”

Voice Solutions

Communicate more effectively with the people you do business with.

CSI Telecommunications, Inc. delivers industry-leading communications solutions to meet the growing demands of today’s business world. Drawing upon our long-standing communications heritage, vast industry expertise and the world-class technology of our partners, CSI Telecommunications, Inc. offers a full spectrum of traditional and next-generation voice services to meet your needs today, and prepare you for tomorrow. Whether you have a large centralized campus, a number of scattered facilities, a number of remote locations, or all of the above, CSI Telecommunications, Inc. can help you select the solution that best fits your current and future needs.

Single Location Solutions

VoIP & Data Solutions

Merge voice and data with cost-effective VoIP solutions

Voice over IP (VoIP) provides businesses with numerous benefits, including improved flexibility, additional functionality, and lower monthly cost. Our knowledgeable expert professionals can assist in planning your IP migration by offering flexible VoIP solutions to help you achieve operational and capital efficiencies, as well as productivity improvement.  CSI Telecommunications, Inc. offers flexible and cost effective VoIP solutions that will seamlessly merge your voice telephone and data technology onto a single network, providing simplicity and reducing costs.

VoIP and Data Bundle

Leverage your existing PBX while gaining a highly functional IP communications solution with a  VoIP and Data Bundle. VoIP and Data Bundle offers the efficiency of VoIP while using your existing PBX. Utilizing dynamic bandwidth allocation, one network serves all your voice, Internet, and WAN needs.


Integrated Services Digital Network (ISDN) is a high-quality, all-digital communications service that gives your business the ability to transmit voice, data, and packet data simultaneously—all at a relatively low-cost.

T1 Bundle

T1 Bundle offers business customers any combination of voice, Internet and networking services T1 Bundle customers enjoy all of the benefits of a bundled package, with the flexibility to precisely meet the needs of their business.

Multiple Location Solutions

MPLS Networking Solutions

MPLS Networking Solutions extend communications across multiple business locations. These solutions enable users to prioritize voice or data through quality of service (QoS) levels, based on their unique business requirements. The carrier’s networking services provide a private, secure multi-site connection built across the carrier’s core MPLS (Multi Protocol Label Switching) advanced IP network, and also feature service level guarantees for latency, jitter and packet loss.

Telecommunications Services

Are you looking for a reliable service/repair company for your current telephone equipment? We have a team of experienced technicians that are capable of service & repair for most major brands of telephone systems. Request a Service Technician or call us today at 636-534-6600.

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