How Does Phone Service Work Through a Cable Company?

By Paul Richard

Cable companies offer telephone services using VoIP.
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Cable television companies provide Internet and telephone services in the highly competitive home entertainment and communications market. Cable companies use Voice over Internet Protocol technologies to transfer phone calls through the cable network. VoIP services normally include local and long distance telephone services for a flat monthly fee, and often include a wide range of options including call waiting, caller ID, three-way calling and other enhanced features.


VoIP technology has opened up telecommunications markets for customers with broadband Internet service. VoIP phone adapters convert an analog telephone signal to digital packets that can be transmitted through the cable network. Calls are routed to servers located near the phone call destination, where the digital signals are converted back to an analog phone conversation. The call is then routed to land line connections, mobile phones or even a satellite for connection to the destination phone. The process is invisible to the customer, but the cable company may control the digital phone conversation through their existing cable network to reduce costs.

What Equipment Does a Cable Customer Need?

Cable customers subscribing to cable voice services will have either a VoIP phone adapter connected to a regular telephone set, or a VoIP-ready telephone with the Internet connectivity installed in the telephone. Customers should ask their cable provider for recommended telephone equipment when they activate phone service. Landline phone service is not necessary when using cable VoIP. The cable connection in the home or business transmits the phone signal.

Can I Make Calls While Surfing the Internet or Watching TV?

Cable broadband services contain adequate bandwidth to allow customers to talk on the telephone while using the Internet connection or watching cable TV. There should be no loss in performance if the system is installed correctly.

What Advantages Are There For Using Cable VoIP?

Existing cable customers adding VoIP services may find discounts available from their cable company. New cable customers will often find package discounts for bundling television, Internet and phone services that are installed and activated at the same time. All customers receive the benefit of having their television, Internet and phone services on a single bill. Telephone voice quality is excellent when making calls over cable networks. Often there are no additional charges to make domestic long-distance calls. Many cable telephone providers offer feature-rich telephone services including conference or three-way calling, caller ID, call waiting, voice mail and other services at no extra cost.