Automated AI Agent Outbound Calling with Twilio - n8n Workflow

• Technical sales operations teams looking to automate high-volume outbound calls.


• Developers needing robust n8n templates for integrating AI agents with traditional telephony.


• Businesses requiring immediate, conversational customer service outreach via phone.


• Users interested in leveraging the n8n node ecosystem for real-time media streaming and automation.

This advanced n8n workflow transforms your automation stack into a powerful call center by integrating Ultravox’s conversational AI with Twilio’s telephony services. This n8n template solves the complex challenge of connecting real-time AI speech generation to the Public Switched Telephone Network (PSTN). The resulting solution enables fully automated outreach campaigns, customer qualification calls, or proactive customer service—all managed seamlessly within a single n8n workflow. By using a specific sequence of n8n node operations, you ensure that the AI conversation is streamed directly and instantaneously to the recipient, leveraging the full potential of n8n automation.

The process begins with the Start Manually n8n trigger, initiating the outbound call sequence. Next, the Set Params n8n node defines the necessary configurations, including the Ultravox agentid, the Twilio source number (twilionumber), and the recipient’s destination phone_number.

The Create Ultravox Call n8n node then sends an authenticated POST request to the Ultravox API, which initiates the AI agent session. This request returns a unique connection string, specifically a joinUrl, which represents the real-time audio stream from the AI agent.

Finally, the Twilio Call n8n node executes the outbound call using the numbers defined previously. Crucially, this n8n node utilizes TwiML (Twilio Markup Language) instructions to connect the live call directly to the joinUrl received from Ultravox. This seamless connection enables the AI agent to converse instantly with the called party, completing the full automated outreach provided by this sophisticated n8n workflow.

1. Import the n8n Workflow: Copy the provided JSON and import it into your n8n instance.


2. Set up Twilio:

1. Define Target: In the Set Params n8n node, replace +1xxxxxxx with the target phone_number you wish to call.


2. Execution: Execute the n8n workflow using the Start Manually n8n trigger to test the automated call.

Start Manually (n8n trigger): Initiates the flow execution manually, perfect for testing this specific n8n workflow or triggering via webhooks in a production environment.
Set Params (Set n8n node): Used to centralize and define crucial variables needed throughout the n8n workflow: agentid (Ultravox Agent ID), twilionumber (source phone number), and phone_number (target destination).
Create Ultravox Call (HTTP Request n8n node): Makes an authenticated POST request to the Ultravox API to start the AI conversation session. The key configuration here is capturing the output's joinUrl required for connecting Twilio's media stream.
Twilio Call (Twilio n8n node): The final action n8n node. It makes the outbound call using the numbers set in Set Params. The message parameter is configured with TwiML to immediately connect the call stream () to the Ultravox server, allowing the AI agent to take over the conversation.