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Voice (IVR)
Early accessVoice (IVR)

Voice (IVR) overview

Answer and place phone calls with a flow built on the canvas, running on your own carrier account.

A Voice (IVR) project answers phone calls. A customer rings your number, your flow picks up, plays a menu, takes what they press or say, checks whatever it needs to against your own systems, and puts them through to the right person, or handles the whole thing itself.

It is the same canvas you build chatbots on. The nodes differ because a phone call differs: there is no screen, the caller cannot scroll back, and silence means something. Variables, API calls, data stores, versioned publishing and the simulator work the way they already do.

A new Voice (IVR) project's canvas with the starter flow: Incoming Call, Main Menu, two Play Message nodes and End Call
Every new Voice (IVR) project starts with this flow.

When to use IVR rather than chat

Reach them byWhen
IVRThey are already calling you. Phone support lines, order status, appointment reminders, payment collection, after-hours routing.
USSDThey have a feature phone and no data. Menus dialled as *384#.
ChatbotsThey are on WhatsApp, web chat, Telegram, Messenger, Instagram or Slack.

A workspace commonly runs more than one. A bank might answer calls with an IVR, serve feature phones over USSD, and run a WhatsApp assistant: three projects, one team, one canvas. See Choose a project type.

What a call does

  1. A carrier receives the call. Twilio, Infobip or Africa's Talking, on your account and your number.
  2. The carrier posts to your project's webhook, which is bound to a phone number on the Routes page.
  3. The shared voice runtime answers, loads your published flow, and runs one turn: play a prompt, wait for a keypress, transfer, record, hang up.
  4. The caller responds, the carrier reports it, and the next turn runs.
  5. The call ends and a call record is written: who called, how long, which nodes it reached, and how it ended.

You never deploy a server. Publishing compiles the flow into a version the shared runtime reads.

Two directions

Inbound starts at an Incoming Call node when someone rings your number.

Outbound starts at an Outbound Call node when the project places a call. See Outbound calls.

A project can do both. They are separate entry points on the same canvas, and a project holds at most one of each.

Nodes

A Voice (IVR) project offers two families: nodes built for phone calls, and channel-agnostic nodes you already use elsewhere, such as Router, API, Data Store, Date & Time and Function. Chat-only nodes (Reply, Intent, Live Chat, Messaging, Form) are not offered, because they have no meaning on a call.

Triggers

Incoming CallWhere every inbound call to this project starts. Plays an optional greeting before the flow continues.Outbound CallWhere a call this project places begins, such as when an agent uses Call and speak it from the Inbox.

Voice

Play MessageSpeaks a message to the caller, or plays uploaded audio or an audio URL, then continues.Menu (voice)Plays a menu and branches on the key the caller presses, with paths for an unrecognised key and for no input.Collect InputAsks the caller for digits or speech and stores the answer in a variable.QueueHolds the caller until someone on your team is free, telling them where they stand while they wait.TransferConnects the caller to a phone number, a SIP endpoint or an available agent, with a fallback path when nobody answers.Warm TransferCalls the agent first and tells them who is waiting. They press a key to accept, or the caller returns to the flow.RecordRecords the caller, as voicemail that ends the call or as a recording the flow continues past.Verify CallerTexts a one-time code to the caller and marks the call verified when they key it in. Protected AI tools require this.End CallEnds the call, optionally after a farewell message.

AI

AI AgentAn LLM agent that understands intent, answers from your knowledge base and calls APIs, integrations and data stores.AI Voice AgentHolds a spoken conversation with the caller, with limits on length and cost and a handoff path to a person.

Logic

RouterSends the flow down one of several paths based on conditions you define.Set FieldsSets or transforms state variables by assigning expressions to named fields.FilterContinues only when a condition is true, and stops the run quietly otherwise.FunctionRuns your own JavaScript and passes its return value to the next node.WaitPauses the workflow for a fixed duration before continuing.Date & TimeGets the current time, formats and parses dates, adds or subtracts durations and computes differences.ErrorShows the user a message when their input is invalid, then lets them try again.

Data

Data StoreCreates, reads, updates and deletes records in one of your data stores.Remove DuplicatesRemoves duplicate items from a list in state, optionally comparing one field.

Integrations

APICalls any HTTP endpoint and passes the response to the next node.IntegrationRuns an action in a connected service such as Salesforce, HubSpot, Google Sheets or Slack, without AI.Collect PaymentRequests a payment by mobile money prompt or card checkout link, on USSD, chat or a call.

Handles, and why the muted ones matter

Voice nodes carry more than one exit. The bright handle is the happy path; muted handles are what happens when a call does not go that way:

NodeMuted handles
Menu (voice)invalid (wrong key), no input (silence)
Collect Inputinvalid, no input
Queuewaited too long
Transferno answer / busy
Warm Transferhanded back (they declined), no answer / busy
Verify Callerfailed
Outbound Callvoicemail, no answer
AI Voice Agenthandoff

A caller reaches a muted handle on an ordinary call: they were in a noisy market, the agent was on another line, the number went to voicemail. Leaving these unwired is the most common reason a flow feels broken to whoever is on the phone. The canvas flags most of them as you build.

What you need before starting

  • A carrier account (Twilio, Infobip or Africa's Talking) with a phone number you control, saved as a credential on the project. Calls run on your account, so the carrier bills you for them.
  • Nothing else to get started. Prompts use the carrier's own text-to-speech out of the box. AI voices and speech-recognition engines are optional and configured in Voice settings.

Your plan also sets limits on voice minutes, phone numbers and concurrent calls. See Billing and usage.

Where to go next

Quick start

A working call flow, tested in the browser, then on a real number.

Node reference

Every node you can put on the canvas.

Carrier setup

Connect a real phone number.

Voice carriers

What each supported carrier can do.
Last reviewed 25 September 2026

Going live

Publish a USSD project, give its Callback URL to your aggregator, and record the short code on the Routes page.

Quick start

Build a working phone menu, test it in the browser simulator, then connect it to a real phone number.

On this page

When to use IVR rather than chatWhat a call doesTwo directionsNodesHandles, and why the muted ones matterWhat you need before startingWhere to go next