> For the complete documentation index, see [llms.txt](https://docs.voiceb.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.voiceb.ai/api-click-to-call/warm-up-sms-for-outbound-calls.md).

# Warm-up SMS for outbound calls

Send leads a text message a few minutes before the agent calls them, so they recognize the number and pick up.

***

## Warm-up SMS

Warm-up SMS sends a text message to the lead shortly before the agent calls. The lead knows the call is coming — and who it's from — which reduces rejected calls from unknown numbers and improves pickup rates.

> Hi {{name}}, this is \[YourBrand]. We'll be calling you in the next few minutes to help you with your request.

### How it works

When a call is scheduled in a campaign with Warm-up SMS enabled, the system sends the SMS at the time you configured before the call — anywhere from 1 minute up to 1 week in advance. The agent then places the call as planned.

If the call is cancelled or rescheduled before it goes out, the pending SMS is cancelled automatically. Leads never receive a "we'll call you shortly" message for a call that isn't going to happen.

### Setting it up

Warm-up SMS is configured per campaign, from the campaign settings:

1. Open the campaign and go to its **configuration**.
2. Turn on **Send a warm-up message before calling**.
3. **Sender number** — select the DDI the SMS will be sent from. Only SMS-capable numbers from your organization are listed.
4. **Time before the call** — define how long before the call the SMS is sent (from 1 minute up to 1 week).
5. **Message** — write the text of the SMS. You can use `{{token}}` placeholders (for example `{{name}}`), which are automatically replaced with the lead and call variables.

<figure><img src="https://2950912279-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FggIr2RvhGm49D4vbjurT%2Fuploads%2FHuHnlU8fubC3YKhxJOti%2FScreenshot%202026-08-18%20at%2010.52.18.png?alt=media&amp;token=5dafa99c-b967-44f5-ae34-aca104c8e705" alt=""><figcaption></figcaption></figure>

#### Requirements & pricing

Warm-up SMS requires a **dedicated SMS-only DDI** — the sender number your leads will see. This is a separate number from your voice DDIs, billed monthly:

| Region                      | Price / Month |
| --------------------------- | ------------- |
| USA                         | $1.50         |
| UK                          | £2.50         |
| All other supported markets | €6.00         |

For sender numbers in other markets, contact Customer Success. Once provisioned, the number appears in the **Sender number** selector of your campaign configuration.

The SMS messages themselves are included — you only pay the monthly fee for the SMS-capable number.

### Good to know

* Warm-up SMS is available for **Click to Call** agents, in campaigns where the warm-up option is enabled. It requires an SMS-capable DDI (see Requirements & pricing above).
* If the call is cancelled or rescheduled before going out, the pending SMS is cancelled automatically — no manual cleanup needed.
* The warm-up message is currently sent over **SMS only**. WhatsApp is not supported yet.

### Tips for writing the message

* Keep it short: who you are, and that a call is coming in a few minutes.
* Always include your brand name, so the lead connects the SMS with the incoming call.
* Use placeholders like `{{name}}` to make the message personal.


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