The default Callplane telephony stack — proven, global, programmable.
Twilio is the default telephony stack for Callplane and the most battle-tested option for production voice agents. Callplane runs the WebSocket media stream against Twilio Voice, handles SIP termination, and orchestrates STT/LLM/TTS so you don't have to write a single line of Twilio glue code.
A voice AI assistant is only useful when it can connect to the rest of your stack. The Twilio integration helps Callplane fit into the systems your team already uses for calling, transcription, reasoning, speech, routing, or customer data. That means the assistant can move from a demo into a production workflow without forcing you to replace your existing tools.
Callplane keeps the integration flexible. You can run one assistant with Twilio, pair it with other providers for a full voice pipeline, and change providers later if your cost, latency, coverage, or quality requirements change. This is especially useful for teams that need different settings per assistant, region, campaign, or customer segment.
The result is a voice agent that is easier to operate: fewer hard-coded assumptions, clearer provider boundaries, and a pricing model that separates Callplane's platform fee from the third-party services you already trust.
Choose Twilio when you need global PSTN coverage, deep DID inventory, or you already have Twilio infrastructure. For US-heavy deployments where you want lower per-minute carrier cost, consider Telnyx instead.
# .env
TWILIO_ACCOUNT_SID=AC...
TWILIO_AUTH_TOKEN=...
TWILIO_PHONE_NUMBER=+15555550100
# In Callplane dashboard: Telephony -> Add Provider -> Twilio
# Callplane auto-configures the voice webhook + media stream URL.For full setup, see the docs.
Callplane: $0.03/min platform fee. Twilio: ~$0.0085/min inbound, ~$0.013/min outbound (US, varies by destination), plus $1/mo per phone number. With BYO mode, you pay Twilio directly at their wholesale rates — Callplane adds zero markup.