Place an outbound call

POST

telephony

sip-trunks

{trunkId}

outbound-call

Place an outbound call

curl --request POST \
  --url https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call \
  --header 'Content-Type: application/json' \
  --header 'X-API-Key: <api-key>' \
  --data '
{
  "agent": {
    "agent_id": "abc123",
    "client_env": "live",
    "variant_id": "default"
  },
  "to_number": "+447700900123",
  "caller_id": "+447700900000",
  "country_code": "GB",
  "metadata": {
    "campaign_id": "spring-sale",
    "customer_ref": "cust-42"
  }
}
'

import requests

url = "https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call"

payload = {
    "agent": {
        "agent_id": "abc123",
        "client_env": "live",
        "variant_id": "default"
    },
    "to_number": "+447700900123",
    "caller_id": "+447700900000",
    "country_code": "GB",
    "metadata": {
        "campaign_id": "spring-sale",
        "customer_ref": "cust-42"
    }
}
headers = {
    "X-API-Key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'X-API-Key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    agent: {agent_id: 'abc123', client_env: 'live', variant_id: 'default'},
    to_number: '+447700900123',
    caller_id: '+447700900000',
    country_code: 'GB',
    metadata: {campaign_id: 'spring-sale', customer_ref: 'cust-42'}
  })
};

fetch('https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'agent' => [
        'agent_id' => 'abc123',
        'client_env' => 'live',
        'variant_id' => 'default'
    ],
    'to_number' => '+447700900123',
    'caller_id' => '+447700900000',
    'country_code' => 'GB',
    'metadata' => [
        'campaign_id' => 'spring-sale',
        'customer_ref' => 'cust-42'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-API-Key: <api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call"

	payload := strings.NewReader("{\n  \"agent\": {\n    \"agent_id\": \"abc123\",\n    \"client_env\": \"live\",\n    \"variant_id\": \"default\"\n  },\n  \"to_number\": \"+447700900123\",\n  \"caller_id\": \"+447700900000\",\n  \"country_code\": \"GB\",\n  \"metadata\": {\n    \"campaign_id\": \"spring-sale\",\n    \"customer_ref\": \"cust-42\"\n  }\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("X-API-Key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call")
  .header("X-API-Key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"agent\": {\n    \"agent_id\": \"abc123\",\n    \"client_env\": \"live\",\n    \"variant_id\": \"default\"\n  },\n  \"to_number\": \"+447700900123\",\n  \"caller_id\": \"+447700900000\",\n  \"country_code\": \"GB\",\n  \"metadata\": {\n    \"campaign_id\": \"spring-sale\",\n    \"customer_ref\": \"cust-42\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["X-API-Key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"agent\": {\n    \"agent_id\": \"abc123\",\n    \"client_env\": \"live\",\n    \"variant_id\": \"default\"\n  },\n  \"to_number\": \"+447700900123\",\n  \"caller_id\": \"+447700900000\",\n  \"country_code\": \"GB\",\n  \"metadata\": {\n    \"campaign_id\": \"spring-sale\",\n    \"customer_ref\": \"cust-42\"\n  }\n}"

response = http.request(request)
puts response.read_body

{
  "call_sid": "OUT-3f2a7c9e-1b4d-4e6a-9c8b-2d5f7a1e0c34"
}

{
  "success": true,
  "error": "<string>",
  "message": "<string>"
}

{
  "success": true,
  "error": "<string>",
  "message": "<string>"
}

{
  "success": true,
  "error": "<string>",
  "message": "<string>"
}

{
  "success": true,
  "error": "<string>",
  "message": "<string>"
}

Place an outbound call that routes over a SIP Trunk. PolyAI dials to_number and connects the answered call to the specified agent.

Use this endpoint to place calls over your own connected SIP Trunk. To place calls over PolyAI-managed telephony instead, use the Agents API Trigger an outbound call endpoint.

Set the trunk’s outbound.default_caller_id and the SIP addresses your calls route to with Update a SIP Trunk. See Connecting to PolyAI Telephony for the outbound transport details.

Destination number

Provide to_number in one of two ways:

Form	Example	Notes
E.164	`to_number: "+447700900123"`	Recommended. No `country_code` needed.
National	`to_number: "07700900123"`, `country_code: "GB"`	`country_code` is an ISO 3166-1 alpha-2 code used to parse the national number.

country_code is optional. Only supply it when to_number is a national number that needs a region to be parsed — for a full E.164 number, leave it out. The caller_id you present must be in E.164. If you omit it, the trunk’s default caller ID is used. The response returns a call_sid (prefixed with OUT-). Use it with Get outbound call status to monitor the call.

Authorizations

X-API-Key

string

header

required

Path Parameters

trunkId

string

required

The SIP Trunk's friendly ID (e.g. tr-...).

Body

application/json

The details of the outbound call to place.

agent

object

required

The PolyAI agent that handles the outbound call.

Show child attributes

to_number

string

required

The destination phone number in E.164, or a national number when country_code is supplied.

Example:

"+447700900123"

caller_id

string

Optional caller ID to present on the call, in E.164 (e.g. +447700900123). If omitted, the trunk's default caller ID is used.

Example:

"+447700900000"

country_code

string

ISO 3166-1 alpha-2 country code used to parse a national to_number.

Example:

"GB"

metadata

object

Optional metadata attached to the call. The encoded payload is capped at roughly 26 KB.

Show child attributes

Example:

{
  "campaign_id": "spring-sale",
  "customer_ref": "cust-42"
}

Response

The call was accepted and queued.

The result of placing an outbound call.

call_sid

string

required

Identifier for the placed call; use it to query the call status. Prefixed with OUT-.

Example:

"OUT-3f2a7c9e-1b4d-4e6a-9c8b-2d5f7a1e0c34"

Last modified on September 3, 2026

⌘I

Place an outbound call

curl --request POST \
  --url https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call \
  --header 'Content-Type: application/json' \
  --header 'X-API-Key: <api-key>' \
  --data '
{
  "agent": {
    "agent_id": "abc123",
    "client_env": "live",
    "variant_id": "default"
  },
  "to_number": "+447700900123",
  "caller_id": "+447700900000",
  "country_code": "GB",
  "metadata": {
    "campaign_id": "spring-sale",
    "customer_ref": "cust-42"
  }
}
'

import requests

url = "https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call"

payload = {
    "agent": {
        "agent_id": "abc123",
        "client_env": "live",
        "variant_id": "default"
    },
    "to_number": "+447700900123",
    "caller_id": "+447700900000",
    "country_code": "GB",
    "metadata": {
        "campaign_id": "spring-sale",
        "customer_ref": "cust-42"
    }
}
headers = {
    "X-API-Key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'X-API-Key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    agent: {agent_id: 'abc123', client_env: 'live', variant_id: 'default'},
    to_number: '+447700900123',
    caller_id: '+447700900000',
    country_code: 'GB',
    metadata: {campaign_id: 'spring-sale', customer_ref: 'cust-42'}
  })
};

fetch('https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'agent' => [
        'agent_id' => 'abc123',
        'client_env' => 'live',
        'variant_id' => 'default'
    ],
    'to_number' => '+447700900123',
    'caller_id' => '+447700900000',
    'country_code' => 'GB',
    'metadata' => [
        'campaign_id' => 'spring-sale',
        'customer_ref' => 'cust-42'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-API-Key: <api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call"

	payload := strings.NewReader("{\n  \"agent\": {\n    \"agent_id\": \"abc123\",\n    \"client_env\": \"live\",\n    \"variant_id\": \"default\"\n  },\n  \"to_number\": \"+447700900123\",\n  \"caller_id\": \"+447700900000\",\n  \"country_code\": \"GB\",\n  \"metadata\": {\n    \"campaign_id\": \"spring-sale\",\n    \"customer_ref\": \"cust-42\"\n  }\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("X-API-Key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call")
  .header("X-API-Key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"agent\": {\n    \"agent_id\": \"abc123\",\n    \"client_env\": \"live\",\n    \"variant_id\": \"default\"\n  },\n  \"to_number\": \"+447700900123\",\n  \"caller_id\": \"+447700900000\",\n  \"country_code\": \"GB\",\n  \"metadata\": {\n    \"campaign_id\": \"spring-sale\",\n    \"customer_ref\": \"cust-42\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.us.poly.ai/v1/telephony/sip-trunks/{trunkId}/outbound-call")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["X-API-Key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"agent\": {\n    \"agent_id\": \"abc123\",\n    \"client_env\": \"live\",\n    \"variant_id\": \"default\"\n  },\n  \"to_number\": \"+447700900123\",\n  \"caller_id\": \"+447700900000\",\n  \"country_code\": \"GB\",\n  \"metadata\": {\n    \"campaign_id\": \"spring-sale\",\n    \"customer_ref\": \"cust-42\"\n  }\n}"

response = http.request(request)
puts response.read_body

{
  "call_sid": "OUT-3f2a7c9e-1b4d-4e6a-9c8b-2d5f7a1e0c34"
}

{
  "success": true,
  "error": "<string>",
  "message": "<string>"
}

{
  "success": true,
  "error": "<string>",
  "message": "<string>"
}

{
  "success": true,
  "error": "<string>",
  "message": "<string>"
}

{
  "success": true,
  "error": "<string>",
  "message": "<string>"
}

API reference

Build & deploy

Runtime & data

Monitoring

Legacy

Destination number

Authorizations

Path Parameters

Body

Response

​Destination number

Authorizations

Path Parameters

Body

Response

Destination number