Outbound Trunks#

Use the Outbound Trunks resource to create, retrieve, update, and delete SIP trunks used for outbound calling through DIDWW.

An Outbound Trunk defines how outbound calls are authenticated and controlled. Its configuration can specify allowed SIP and RTP addresses, CLI policies, destination-prefix rules, simultaneous-call and 24-hour spending limits, media settings, status, callbacks, and DIDs allowed for regular or emergency calling.

Outbound Trunks support credentials_and_ip, ip_only, and twilio authentication when retrieved. New or updated trunks can use credentials_and_ip or twilio; ip_only cannot be selected through POST or PATCH.

Note

The Outbound feature is not enabled by default. In version 2026-04-16, Outbound Trunks can be created or updated and their credentials can be regenerated through the API even when the feature is not enabled. For more information, contact DIDWW Sales.

Endpoints#

Action

Method

Endpoint

Retrieve all Outbound Trunks

GET

/v3/voice_out_trunks

Retrieve Outbound Trunk

GET

/v3/voice_out_trunks/{id}

Create Outbound Trunk

POST

/v3/voice_out_trunks

Update Outbound Trunk

PATCH

/v3/voice_out_trunks/{id}

Delete Outbound Trunk

DELETE

/v3/voice_out_trunks/{id}

Regenerate Outbound Trunk credentials

POST

/v3/voice_out_trunk_regenerate_credentials

Retrieve all Outbound Trunks#

Retrieves all Outbound Trunks configured for the account.

Use this endpoint to filter trunks by name, external reference ID, authentication type, CLI policy, status, threshold state, destination policy, media encryption, or Emergency Calling configuration. Related regular and emergency DIDs can be included in the response.

See Retrieve All Outbound Trunks.

GET /v3/voice_out_trunks

Retrieve Outbound Trunk#

Retrieves a specific Outbound Trunk by its unique ID.

Use this endpoint to inspect the trunk’s authentication, call policies, limits, media configuration, status, and related DIDs.

See Retrieve Outbound Trunk.

GET /v3/voice_out_trunks/{id}

Create Outbound Trunk#

Creates an Outbound Trunk using credentials_and_ip or twilio authentication.

Use this endpoint to configure authentication, allowed network addresses, CLI handling, destination rules, limits, media behavior, callbacks, and DIDs allowed for regular or emergency calling. The ip_only authentication type cannot be used when creating a trunk.

See Create Outbound Trunk.

POST /v3/voice_out_trunks

Update Outbound Trunk#

Updates a specific Outbound Trunk.

Use this endpoint to change the trunk’s configuration, authentication type, call policies, limits, status, callbacks, or related DIDs. When the authentication type is changed, the previous authentication attributes are cleared. The authentication type cannot be changed to ip_only.

See Update Outbound Trunk.

PATCH /v3/voice_out_trunks/{id}

Delete Outbound Trunk#

Permanently deletes a specific Outbound Trunk. A deleted trunk cannot be retrieved.

See Delete Outbound Trunk.

DELETE /v3/voice_out_trunks/{id}

Regenerate Outbound Trunk credentials#

Regenerates the username and password for an Outbound Trunk that uses credentials_and_ip authentication.

This endpoint does not apply to trunks that use ip_only or twilio authentication.

See Regenerate Outbound Trunk Credentials.

POST /v3/voice_out_trunk_regenerate_credentials

Data reference#

See Outbound Trunk Object for the complete trunk attributes, authentication objects, and DID relationships.

Common Outbound Trunk use cases#

Use case

Description

Configure SIP authentication

Authenticate calls using SIP credentials with allowed IP addresses or a Twilio Account SID.

Restrict originating addresses

Define the SIP and RTP IP addresses allowed to send signaling and media traffic.

Control outbound CLI

Assign eligible DIDs and define how calls are handled when the presented CLI does not match the allowed DID list.

Control called destinations

Allow or reject destinations according to the default action and configured prefix exceptions.

Manage trunk availability

Set the trunk status to active or blocked.

Apply usage limits

Configure a simultaneous-call limit and a 24-hour threshold amount.

Configure media handling

Set allowed RTP addresses, media encryption, symmetric RTP, RTP ping, and timeout behavior.

Configure Emergency Calling

Allow all eligible DIDs or select specific emergency-enabled DIDs for Emergency Calling through the trunk.

Regenerate credentials

Replace the username and password for a credentials_and_ip trunk.