---
title: "Send a message using an alphanumeric sender ID"
method: POST
path: "/messages/alphanumeric/sender/id"
tags: ["Messages"]
---

# Send a message using an alphanumeric sender ID

`POST /messages/alphanumeric/sender/id`

## Request

- Base URL: `https://api.telnyx.com/v2`
- URL: `https://api.telnyx.com/v2/messages/alphanumeric/sender/id`
- Auth: HTTP bearer

Send an SMS message using an alphanumeric sender ID. This is SMS only.

## Request body

- object
  - `from` string, required: A valid alphanumeric sender ID on the user's account.
  - `to` string, required: Receiving address (+E.164 formatted phone number or short code).
  - `text` string, required: The message body.
  - `messaging_profile_id` string, uuid, required: The messaging profile ID to use.
  - `webhook_url` string, url, nullable: Callback URL for delivery status updates.
  - `webhook_failover_url` string, url, nullable: Failover callback URL for delivery status updates.
  - `use_profile_webhooks` boolean: If true, use the messaging profile's webhook settings.

## Response `200`

Successful response with the sent message.

- OutboundMessageResponse
  - `data` OutboundMessagePayload
    - `record_type` 'message': Identifies the type of the resource.
    - `direction` 'outbound': The direction of the message. Inbound messages are sent to you whereas outbound messages are sent from you.
    - `id` string, uuid: Identifies the type of resource.
    - `type` 'SMS' | 'MMS': The type of message.
    - `messaging_profile_id` string: Unique identifier for a messaging profile.
    - `organization_id` string, uuid: The id of the organization the messaging profile belongs to.
    - `from` object
      - `phone_number` string: Sending address (+E.164 formatted phone number, alphanumeric sender ID, or short code).
      - `carrier` string: The carrier of the receiver.
      - `line_type` 'Wireline' | 'Wireless' | 'VoWiFi' | 'VoIP' | 'Pre-Paid Wireless' | '': The line-type of the receiver.
    - `to` object[]
      - `phone_number` string: Receiving address (+E.164 formatted phone number or short code).
      - `status` 'queued' | 'sending' | 'sent' | 'expired' | 'sending_failed' | 'delivery_unconfirmed' | 'delivered' | 'delivery_failed': The delivery status of the message.
      - `carrier` string: The carrier of the receiver.
      - `line_type` 'Wireline' | 'Wireless' | 'VoWiFi' | 'VoIP' | 'Pre-Paid Wireless' | '': The line-type of the receiver.
    - `cc` object[]
      - `phone_number` string: Receiving address (+E.164 formatted phone number or short code).
      - `status` 'queued' | 'sending' | 'sent' | 'delivered' | 'sending_failed' | 'delivery_failed' | 'delivery_unconfirmed'
      - `carrier` string: The carrier of the receiver.
      - `line_type` 'Wireline' | 'Wireless' | 'VoWiFi' | 'VoIP' | 'Pre-Paid Wireless' | '': The line-type of the receiver.
    - `text` string: Message body (i.e., content) as a non-empty string. **Required for SMS**
    - `num_chars` integer: The number of characters in the message text
    - `subject` string, nullable: Subject of multimedia message
    - `media` object[]
      - `url` string, url: The url of the media requested to be sent.
      - `content_type` string, nullable: The MIME type of the requested media.
      - `sha256` string, nullable: The SHA256 hash of the requested media.
      - `size` integer, nullable: The size of the requested media.
    - `webhook_url` string, url, nullable: The URL where webhooks related to this message will be sent.
    - `webhook_failover_url` string, url, nullable: The failover URL where webhooks related to this message will be sent if sending to the primary URL fails.
    - `encoding` string: Encoding scheme used for the message body.
    - `parts` integer: Number of parts into which the message's body must be split.
    - `tags` string[]: Tags associated with the resource.
    - `cost` object, nullable
      - `amount` string: The amount deducted from your account.
      - `currency` string: The ISO 4217 currency identifier.
    - `cost_breakdown` object, nullable: Detailed breakdown of the message cost components.
      - `carrier_fee` object
        - `amount` string: The carrier fee amount.
        - `currency` string: The ISO 4217 currency identifier.
      - `rate` object
        - `amount` string: The rate amount applied.
        - `currency` string: The ISO 4217 currency identifier.
    - `tcr_campaign_id` string, nullable: The Campaign Registry (TCR) campaign ID associated with the message.
    - `tcr_campaign_billable` boolean: Indicates whether the TCR campaign is billable.
    - `tcr_campaign_registered` string, nullable: The registration status of the TCR campaign.
    - `received_at` string, date-time: ISO 8601 formatted date indicating when the message request was received.
    - `sent_at` string, date-time, nullable: ISO 8601 formatted date indicating when the message was sent.
    - `completed_at` string, date-time, nullable: ISO 8601 formatted date indicating when the message was finalized.
    - `valid_until` string, date-time, nullable: Message must be out of the queue by this time or else it will be discarded and marked as 'sending_failed'. Once the message moves out of the queue, this field will be nulled
    - `errors` MessagingError[]: These errors may point at addressees when referring to unsuccessful/unconfirmed delivery statuses.
      - `code` string, required
      - `title` string, required
      - `detail` string
      - `source` object
        - `pointer` string, json-pointer: JSON pointer (RFC6901) to the offending entity.
        - `parameter` string: Indicates which query parameter caused the error.
      - `meta` object
    - `smart_encoding_applied` boolean: Indicates whether smart encoding was applied to this message. When `true`, one or more Unicode characters were automatically replaced with GSM-7 equivalents to reduce segment count and cost. The original message text is preserved in webhooks.
    - `wait_seconds` number, float, nullable: Seconds the message is queued due to rate limiting before being sent to the carrier. Represents the maximum wait across all applicable rate limits (account, carrier, campaign). 0.0 = no queuing delay.

## Other responses

- `400`: Bad Request
- `401`: Unauthorized
- `422`: Unprocessable Entity

## Changes

- **2026-10-15** `a72569d69430`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/team-telnyx/apis/telnyx-api/changes/messages/alphanumeric/sender/id/post.md)

---

[API](https://skmtc.dev/team-telnyx/apis/telnyx-api.md) - [All operations](https://skmtc.dev/team-telnyx/apis/telnyx-api/llms.txt) - [OpenAPI document](https://skmtc.dev/team-telnyx/apis/telnyx-api/revisions/0f17b8167873?raw)