Configure live call transfers to external numbers

Set up AI voice agents to transfer calls to your team with routing rules, warm handoffs, and fallback handling for unavailable numbers.

Call transfer lets your AI voice agent hand off a live call to a human team member when the situation requires it. The agent can transfer based on caller requests, qualification outcomes, or specific keywords — routing to different numbers depending on the context. The caller stays on the line during the transfer with no disconnection.

How call transfer works

1. During a live call, the agent detects a transfer trigger (keyword, qualification result, or direct request).
2. The agent plays a pre-transfer notification message to the caller.
3. The agent dials the destination number and, if warm transfer is enabled, delivers a context summary to the receiving person.
4. The caller is connected to the human agent.
5. The AI agent disconnects from the call.

Set up call transfer

1. Open your agent in the Agent Builder

   Navigate to AI Agents and click the voice agent you want to configure.

2. Enable the Transfer to Human tool

   Go to the Tools tab. Find Transfer to Human and toggle it on. Enter the destination phone number — this is where calls will be routed.

3. Add transfer instructions to your prompt

   In the Prompt tab, define when and how the agent should transfer. Be specific about the conditions:

   TRANSFER RULES:
   - Transfer immediately if the caller says "speak to a human" or "talk to someone"
   - Transfer if the caller is an existing patient asking about test results
   - Transfer to the sales team if the caller is a qualified lead ready to purchase
   - Never transfer for general information questions — handle those yourself

4. Configure the pre-transfer message

   Tell the agent what to say before initiating the transfer:

   Before transferring, say: "I'm going to connect you with a member of our team
   who can help you with this. Please stay on the line for just a moment."

5. Test the transfer in Voice Lab

   Open Voice Lab and simulate scenarios that should trigger a transfer. Verify the agent transfers at the right moment and delivers the correct pre-transfer message.

Set transfer triggers

Define specific conditions in your prompt that tell the agent when to transfer:

Trigger type	Example	Prompt instruction
Keyword	”speak to a human”	Transfer when the caller says “speak to a human,” “talk to someone,” or “real person”
Qualification outcome	Lead is qualified and ready to buy	Transfer qualified leads who confirm they want to proceed today
Topic-based	Medical emergency	Transfer immediately if the caller describes an emergency — do not ask further questions
User request	Direct ask	Transfer whenever the caller explicitly requests to speak to a team member
Frustration detection	Repeated objections	Transfer if the caller expresses frustration or repeats the same concern three times

Route to multiple numbers

You can configure different transfer destinations based on the context of the call. Define routing rules in your prompt:

TRANSFER ROUTING:
- Sales inquiries → transfer to +1-555-0101 (Sales Team)
- Support issues → transfer to +1-555-0102 (Support Team)
- Billing questions → transfer to +1-555-0103 (Billing Department)
- All other transfer requests → transfer to +1-555-0100 (Main Office)

Warm transfer with context summary

A warm transfer means the agent briefly speaks to the receiving person before connecting the caller. This gives your team context about the call so the caller doesn’t have to repeat themselves.

Add warm transfer instructions to your prompt:

WARM TRANSFER INSTRUCTIONS:
When transferring, first tell the receiving team member:
- The caller's name
- What they called about
- Any relevant details collected during the call
- Why the call is being transferred

Example: "Hi, I'm transferring a call from John Smith. He's interested in our
premium plan and has some questions about pricing that need a human touch.
He's been very friendly and is ready to discuss next steps."

Pre-transfer notification messages

Always notify the caller before transferring. This prevents confusion and sets expectations:

PRE-TRANSFER MESSAGES:
- Standard: "Let me connect you with a member of our team. One moment please."
- Sales: "Great news — I'm connecting you with one of our specialists who can
  walk you through everything. Just a moment."
- Support: "I want to make sure you get the best help possible. Let me transfer
  you to our support team right now."
- Unavailable fallback: "It looks like our team is unavailable right now. Can I
  take your details and have someone call you back within the hour?"

Handle unavailable numbers

When the destination number doesn’t answer or is busy, the agent needs a fallback plan. Configure this in your prompt:

IF TRANSFER FAILS:
1. Apologize: "I'm sorry, it looks like our team member isn't available right now."
2. Offer alternatives:
   - "Would you like me to take your details and have someone call you back?"
   - "I can also send you an email with the information you need."
3. If the caller wants a callback, collect their preferred time and use create_notes
   to log the callback request.
4. Never leave the caller hanging — always provide a next step.