Skip to contentSkip to navigationSkip to topbar
Twilio Docs
Page tools
Useful for sharing or LLM
Looking for more inspiration?Visit the

What is the PSTN (Public Switched Telephone Network)?

The PSTN (Publicly Switched Telephone Network) is the network that carries your voice calls when you call from a landline or cell phone. It refers to the worldwide network of voice-carrying telephone infrastructure, including privately-owned and government-owned infrastructure.

Interfacing between the internet and the PSTN has traditionally been costly and difficult. The Twilio Programmable Voice API(link takes you to an external page) abstracts this complexity away, giving developers verbs like <Dial> and <Conference> to execute voice calling tasks that were difficult in the past.