Create SIP trunk

Create a new SIP trunk with credentials, address, and proxy settings

Updated 30 June 2026

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This endpoint creates a new SIP trunk. The platform automatically provisions inbound and outbound trunks on the voice infrastructure using the provided credentials.

Body Parameters

sip_trunk_typestringrequired

The type of SIP trunk: extension for a SIP extension, or number for a phone number (DID). This determines the expected format of the phone_number field.

phone_numberstringrequired

The SIP extension (1-15 characters, e.g. 1000) when sip_trunk_type is extension, or a phone number in E.164 format (e.g. +14155551234) when sip_trunk_type is number.

nicknamestring

A short, human-friendly label for the trunk (e.g. "Provider X — Main"). Maximum 50 characters.

sip_usernamestringrequired

Username for SIP authentication (3-128 characters)

sip_passwordstringrequired

Password for SIP authentication (minimum 3 characters)

sip_addressstringrequired

The SIP server address without port (e.g. sip.provider.com)

sip_calling_formatstringrequired

The outbound calling number format:

+e164 — International with + prefix (e.g. +12025550123)
e164 — International without + prefix (e.g. 12025550123)
national — National format without country code (e.g. 0741926265)

inbound_authorization_typestringrequired

How inbound calls are authenticated:

auth — Uses the same SIP username and password configured for outbound
ip — Whitelists specific IP addresses (requires allowed_inbound_ips)

allowed_inbound_ipsarray

Array of IP addresses allowed to send inbound calls. Required when inbound_authorization_type is ip. Must contain at least one valid IP address.

country_codestringrequired

ISO 3166-2 country code where the SIP trunk is located (e.g. US, GB, DE). When sip_trunk_type is number, the country is auto-detected from the phone number if possible.

outbound_proxyboolean

Route outbound calls through a fixed IP address. Default: false. Only enable this if your SIP provider requires IP-based authentication for outbound traffic.

Response

messagestring

Success message

dataobject

The created SIP trunk object (same fields as Get SIP trunk)

{
  "message": "SIP trunk created successfully.",
  "data": {
    "id": 42,
    "phone_number": "1000",
    "nickname": "Provider X — Main",
    "sip_username": "myuser",
    "sip_address": "sip.provider.com",
    "sip_calling_format": "+e164",
    "inbound_authorization_type": "auth",
    "allowed_inbound_ips": null,
    "outbound_proxy": false,
    "country_code": "US",
    "inbound_trunk_id": "ST_xxxxxxxxxxxx",
    "outbound_trunk_id": "ST_yyyyyyyyyyyy",
    "created_at": "2026-03-31T10:00:00.000000Z",
    "updated_at": "2026-03-31T10:00:00.000000Z"
  }
}

{
  "message": "SIP trunk created successfully.",
  "data": {
    "id": 43,
    "phone_number": "+14155551234",
    "nickname": null,
    "sip_username": "trunk_user",
    "sip_address": "sip.provider.com",
    "sip_calling_format": "e164",
    "inbound_authorization_type": "ip",
    "allowed_inbound_ips": ["203.0.113.10", "198.51.100.20"],
    "outbound_proxy": true,
    "country_code": "US",
    "inbound_trunk_id": "ST_xxxxxxxxxxxx",
    "outbound_trunk_id": "ST_yyyyyyyyyyyy",
    "created_at": "2026-03-31T10:00:00.000000Z",
    "updated_at": "2026-03-31T10:00:00.000000Z"
  }
}

{
  "error": "A SIP trunk with the same phone number, username, and address already exists."
}

{
  "message": "The given data was invalid.",
  "errors": {
    "sip_address": ["SIP server address is required."],
    "sip_calling_format": ["SIP calling format must be one of: +e164, e164, national."]
  }
}

{
  "error": "Failed to create SIP trunk. Please try again or contact support."
}

What happens after creation

When you create a SIP trunk, the platform automatically:

Provisions an inbound trunk on the voice infrastructure — using either username/password or IP-based authentication depending on your inbound_authorization_type setting
Provisions an outbound trunk — using the SIP address and credentials you provided, optionally through the outbound proxy

If provisioning fails, the SIP trunk is not saved and a 500 error is returned.