What is a SIP trunk service and how does it support business communications?

A SIP trunk service enables voice calls to be made over the internet rather than through traditional telephone lines. It connects your organisation’s phone system or cloud unified communications service, such as Microsoft Teams or Webex, to the Public Switched Telephone Network (PSTN) using Session Initiation Protocol (SIP), allowing you to make and receive external calls through your existing IP-based infrastructure.

SIP trunking supports modern business communications by offering:

  • Scalability: Easily add or remove channels as your needs evolve, without the constraints of physical lines.

  • Flexibility: Enable staff to make and receive calls from anywhere, supporting hybrid and remote working.

  • Cost savings: Reduce line rental fees, call charges and ongoing maintenance costs.

  • Reliability: Built-in redundancy and failover routing for improved uptime and resilience.