> ## Documentation Index
> Fetch the complete documentation index at: https://signatureapi-daf4ee54.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Send Signing Links via SMS

> Deliver signing links through SMS or any custom channel using inline ceremonies with short URLs

By default, SignatureAPI sends signing links to recipients via email. If you need to deliver signing links through SMS, WhatsApp, or any other channel, you can disable email delivery and configure an inline ceremony with a short URL directly on the recipient.

This example creates an envelope with:

* A single PDF document with one signature place.
* One recipient with `delivery_type` set to `none` (deliverables are not sent automatically).
* An inline `ceremony` object with custom authentication and `url_variant` set to `short` for SMS-friendly URLs.

## Create the Envelope

Set `delivery_type` to `none` on the recipient so the completed deliverable is not automatically emailed. Include a `ceremony` object on the recipient with `custom` authentication (since your application handles delivery) and set `url_variant` to `short` to generate a compact URL suitable for SMS.

```json theme={null}
// POST https://api.signatureapi.com/v1/envelopes
// X-API-Key: key_test_...
// Content-Type: application/json

{
  "title": "Service Agreement",
  "documents": [
    {
      "url": "https://example.com/documents/agreement.pdf",
      "places": [
        {
          "key": "customer_signature",
          "type": "signature",
          "recipient_key": "customer"
        }
      ]
    }
  ],
  "recipients": [
    {
      "type": "signer",
      "key": "customer",
      "name": "Alex Rivera",
      "email": "alex@example.com",
      "delivery_type": "none",
      "ceremony": {
        "authentication": [
          {
            "type": "custom",
            "provider": "SMS",
            "data": {
              "phone": "+1-555-867-5309"
            }
          }
        ],
        "url_variant": "short"
      }
    }
  ]
}
```

Key properties on the recipient:

* `delivery_type`: Set to `none` so the completed deliverable is not automatically emailed to this recipient. Your application is responsible for distributing the deliverable.
* `ceremony`: Configures the signing ceremony inline. SignatureAPI creates the ceremony automatically when the envelope starts processing.
* `ceremony.authentication`: Uses `custom` type since your application handles delivery. The `provider` and `data` values are recorded in the audit log.
* `ceremony.url_variant`: Set to `short` to generate a compact URL like `https://sign.signatureapi.com/s/BgnexxxxxxxxIbRi`, which fits within SMS character limits.

<Note>
  The recipient still requires an `email` property even when `delivery_type` is `none`. The email is used for identification and audit purposes.
</Note>

## Get the Ceremony URL

The response includes the short ceremony URL in `recipients[].ceremony.url`:

```json theme={null}
// HTTP Status Code 200

{
  "id": "55072f0e-b919-4d69-89cd-e7e56af00530",
  "title": "Service Agreement",
  "recipients": [
    {
      "id": "re_7v7Sion0vqjJioYmwfZ9mf",
      "key": "customer",
      "name": "Alex Rivera",
      "ceremony": {
        "authentication": [
          {
            "type": "custom",
            "provider": "SMS",
            //...
          }
        ],
        "url_variant": "short",
        "url": "https://sign.signatureapi.com/s/BgnexxxxxxxxIbRi"
      },
      //...
    }
  ],
  //...
}
```

## Send the Link via SMS

Take the `url` from the ceremony response and deliver it through your SMS provider (such as Twilio, MessageBird, or Amazon SNS).

```js theme={null}
// Example: sending via Twilio
const ceremonyUrl = response.recipients[0].ceremony.url;

await twilioClient.messages.create({
  to: "+15558675309",
  from: "+15551234567",
  body: `Please sign your Service Agreement: ${ceremonyUrl}`
});
```

The recipient opens the link on their device, reviews the document, and signs.

## Result

When the recipient completes the ceremony, SignatureAPI updates the envelope status as usual. You can track completion through [webhooks](/docs/api/guides/how-to/set-up-webhooks) or by polling the envelope.

## Try It

[Try this example in Postman](/docs/api/postman) using your [test API key](/docs/api/test-mode) to create a free, non-binding test envelope. Test envelopes won't send emails, but you can review them in your dashboard.

## Keep Learning

* Learn more about [short ceremony URLs](/docs/api/resources/ceremonies/ceremony-url#short-ceremony-urls) and when to use them.
* Use [custom authentication](/docs/api/guides/how-to/custom-authentication) to record additional context about how the signer was verified.
* [Embed the signing ceremony](/docs/api/guides/how-to/embed-web) in your own web application instead of redirecting to the SignatureAPI signing page.
* Set up [webhooks](/docs/api/guides/how-to/set-up-webhooks) to receive real-time notifications when signing completes.