> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ouraicalling.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Send SMS

> Send an SMS message using your Famulor phone number via API. Trigger transactional or follow-up texts after AI voice calls, lead capture or campaigns.

<Warning>
  **Famulor 1.0 API (legacy).** This page applies only to Famulor 1.0 (`app.famulor.de`) and is retained for legacy compatibility. For the current platform, use the [Famulor 2.0 API reference](/api-reference/introduction).
</Warning>

This endpoint allows you to send SMS messages via your purchased phone numbers. The SMS is sent through Twilio, and the costs are automatically deducted from your account balance.

### Request Body

<ParamField body="from" type="integer" required>
  The ID of your phone number from which the SMS will be sent (must be SMS-capable)
</ParamField>

<ParamField body="to" type="string" required>
  The recipient's phone number in international format (e.g., "+4915123456789")
</ParamField>

<ParamField body="body" type="string" required>
  The SMS message content (max. 300 characters)
</ParamField>

### Response Fields

<ResponseField name="message" type="string">
  Success message confirming that the SMS was sent
</ResponseField>

<ResponseField name="data" type="object">
  Additional data about the sent SMS
</ResponseField>

### Error Responses

<ResponseField name="400 Bad Request" type="object">
  <Expandable title="Error Details">
    <ResponseField name="message" type="string">
      Error message describing the issue (invalid phone number, insufficient balance, etc.)
    </ResponseField>
  </Expandable>
</ResponseField>

<ResponseField name="500 Internal Server Error" type="object">
  <Expandable title="Server Error">
    <ResponseField name="message" type="string">
      Error message indicating a failure in sending the SMS
    </ResponseField>

    <ResponseField name="error" type="string">
      Detailed error information
    </ResponseField>
  </Expandable>
</ResponseField>

### Notes

* The sender phone number must belong to the authenticated user
* The sender phone number must be SMS-capable
* The phone number subscription must be active (not expired)
* Sufficient account balance is required to cover SMS costs
* Phone numbers are automatically formatted to E.164 format
* SMS costs vary depending on the destination country and are charged per segment
* Long messages can be split into multiple segments, increasing the cost
* The recipient phone number must comply with international standards

<ResponseExample>
  ```json 200 Sent Successfully theme={null}
  {
    "message": "SMS sent successfully",
    "data": {
      "sms_id": "SMS_67890",
      "from": "+4912345678",
      "to": "+4915123456789",
      "body": "Hello! This is a test SMS from Famulor.",
      "segments": 1,
      "cost": 0.05,
      "currency": "EUR",
      "status": "sent"
    }
  }
  ```

  ```json 400 Invalid Request theme={null}
  {
    "message": "Invalid phone number format"
  }
  ```

  ```json 400 Insufficient Balance theme={null}
  {
    "message": "Insufficient balance to send SMS"
  }
  ```

  ```json 400 Phone Number Not SMS-Capable theme={null}
  {
    "message": "Phone number is not SMS-capable"
  }
  ```

  ```json 400 Phone Number Not Found theme={null}
  {
    "message": "From number not found"
  }
  ```

  ```json 500 Server Error theme={null}
  {
    "message": "Failed to send SMS",
    "error": "Twilio service temporarily unavailable"
  }
  ```
</ResponseExample>

<Tip>
  Related pages: [Introduction](/api-v1/introduction) and [Authentication Guide](/api-v1/authentication), and [API Integration Examples](/api-v1/introduction).
</Tip>