Telnyx Wireless: VoLTE — Full Documentation

Complete page content for VoLTE (Wireless section) of the Telnyx developer docs (https://developers.telnyx.com). Root index: https://developers.telnyx.com/llms.txt · Lightweight index for this subsection: https://developers.telnyx.com/development/llms/wireless-volte-llms-txt.md

Overview

Source: https://developers.telnyx.com/docs/iot-sim/voice-enabled-iot.md

Beta — VoLTE is in beta. API reference and detailed configuration docs coming soon. Add a real phone number to any eSIM-capable device. No second phone, no SIP client, no app — just a native cellular line with full API control.

Configuration

Phone Numbers

Source: https://developers.telnyx.com/docs/iot-sim/mobile-phone-numbers.md

When you enable voice on a SIM, Telnyx assigns a Mobile Phone Number — a real +E.164 number. Inbound calls ring the device natively. Outbound calls show your number as caller ID.

Enabling Voice

Voice is enabled per-SIM via action endpoints, not by patching a field.

Action	Endpoint
Enable Voice	`POST /sim_cards/{id}/actions/enable_voice`
Disable Voice	`POST /sim_cards/{id}/actions/disable_voice`
Bulk Enable Voice	`POST /sim_cards/actions/bulk_enable_voice`
Bulk Disable Voice	`POST /sim_cards/actions/bulk_disable_voice`

enable_voice accepts an optional connection_id to associate with a Mobile Voice Connection.

Mobile Phone Number

Once voice is enabled, manage the assigned number via:

Action	Endpoint
List Numbers	`GET /mobile_phone_numbers`
Get Number	`GET /mobile_phone_numbers/{id}`
Update Number	`PATCH /mobile_phone_numbers/{id}`

Configurable Settings

Setting	Description
`call_forwarding`	Forward calls on no-answer, busy, or unconditional
`call_recording`	Record inbound, outbound, or both
`caller_id_name_enabled`	Enable CNAM lookup on outbound calls
`cnam_listing`	Register business name for inbound CNAM display
`noise_suppression`	AI noise reduction on calls
`inbound_call_screening`	Filter inbound calls before connecting
`connection_id`	Associate with a Mobile Voice Connection
`customer_reference`	Your own reference string
`tags`	Arbitrary tags for filtering
`inbound` / `outbound`	Routing configuration per direction

Mobile Voice Connection

The voice application attached to a number — controls webhooks, API version, and routing.

Action	Endpoint
List Connections	`GET /mobile_voice_connections`
Create Connection	`POST /mobile_voice_connections`
Get Connection	`GET /mobile_voice_connections/{id}`
Update Connection	`PATCH /mobile_voice_connections/{id}`
Delete Connection	`DELETE /mobile_voice_connections/{id}`

Connection Settings

Setting	Description
`webhook_event_url`	Where call events are sent
`webhook_event_failover_url`	Backup URL if primary fails
`webhook_timeout_secs`	How long to wait for webhook response
`outbound` / `inbound`	Routing configuration per direction
`active`	Whether the connection is active

Forwarding, Recording & Screening

Source: https://developers.telnyx.com/docs/iot-sim/call-forwarding-recording.md

All settings below are configured via PATCH /mobile_phone_numbers/{id}.

Call Forwarding

Set the call_forwarding object to route calls when the device is unavailable.

Type	Behavior
`unconditional`	All calls forward immediately — device never rings
`no_answer`	Forward after timeout (device rings first)
`busy`	Forward when line is in use

Forward to any number — landline, mobile, SIP connection, or Call Control application.

Call Recording

Set call_recording to record inbound, outbound, or both. Recordings are accessible through the standard Telnyx Recordings API — same storage, retrieval, and webhooks as Call Control recordings.

Inbound Call Screening

Inbound Call Screening automatically blocks or flags inbound calls based on caller reputation and SHAKEN/STIR attestation. The feature is free on any number.

How it works

Screening evaluates three factors:

Factor	Description
Number Reputation	Cross-references caller identity against CallerAPI, Nomorobo, and YouMail databases
Number Validation	Checks whether the originating number is valid and exists
SHAKEN/STIR Attestation	Validates Caller ID authenticity — screens calls with Attestation C (unauthenticated) or Invalid (certificate error)

Handling modes

Mode	Behavior
Flag	Call connects but displays “SPAM LIKELY” in the From and P-Asserted-ID headers. A custom SIP header carries the screening status for your routing logic.
Reject	Call is blocked at the network level and never reaches your infrastructure.

Enabling call screening

Log in to the Mission Control Portal.
Go to My Numbers, select a number, and click Edit.
Under the Voice tab, enable Inbound Call Screening and choose Flag or Reject.

You can also enable it via PATCH /mobile_phone_numbers/{id} by setting the inbound_call_screening field.

Webhook integration

Enable webhooks to receive the call_screening_result field in the call.initiated webhook payload. Number reputation screening applies to US and Canada calls. SHAKEN/STIR screening applies to North America.

Other Settings

Setting	Description
`noise_suppression`	AI noise reduction for loud environments

Example

{
  "call_forwarding": {
    "forwarding_type": "no_answer",
    "forwarding_number": "+15551234567",
    "timeout_secs": 30
  },
  "call_recording": {
    "inbound": "enabled",
    "outbound": "disabled"
  },
  "noise_suppression": "enabled"
}

Overview

Configuration

For AI Agents

VoLTE llms-full.txt

Telnyx Wireless: VoLTE — Full Documentation

Overview

Overview

Configuration

Phone Numbers

Enabling Voice

Mobile Phone Number

Configurable Settings

Mobile Voice Connection

Connection Settings

Forwarding, Recording & Screening

Call Forwarding

Call Recording

Inbound Call Screening

How it works

Handling modes

Enabling call screening

Webhook integration

Other Settings

Example

​Telnyx Wireless: VoLTE — Full Documentation

​Overview

​Overview

​Configuration

​Phone Numbers

​Enabling Voice

​Mobile Phone Number

​Configurable Settings

​Mobile Voice Connection

​Connection Settings

​Forwarding, Recording & Screening

​Call Forwarding

​Call Recording

​Inbound Call Screening

​How it works

​Handling modes

​Enabling call screening

​Webhook integration

​Other Settings

​Example

Telnyx Wireless: VoLTE — Full Documentation

Overview

Overview

Configuration

Phone Numbers

Enabling Voice

Mobile Phone Number

Configurable Settings

Mobile Voice Connection

Connection Settings

Forwarding, Recording & Screening

Call Forwarding

Call Recording

Inbound Call Screening

How it works

Handling modes

Enabling call screening

Webhook integration

Other Settings

Example