# SMS

The **SMS** tool allows you to build a workflow that sends an SMS message in seconds. You can customize the phone number and edit the message by using [Variables](https://docs.getmesa.com/workflow-builder/fields/variables). All messages will be sent from this phone number +1 510 567 7078.

{% hint style="info" %}
**SMS** is a Premium app. There is a limit to the number of Premium actions we provide for free. [Learn more](https://docs.getmesa.com/going-further/plans-and-billing#premium-steps)
{% endhint %}

<figure><img src="https://3425906282-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1H6u1HQc3Iew7ATmmiCi%2Fuploads%2FxvOzmPHBzFpHTDjvmOFQ%2FEF-sms.png%20-%20Step%202.png?alt=media&#x26;token=09f0e2fb-8967-460f-9cab-d61ee393cea7" alt=""><figcaption></figcaption></figure>

## Prohibited messages

All messages must adhere to the [codes of conduct published by mobile network operators](https://www.10dlc.org/en/verizon-tmobile-att-sprint-carrier-code-of-conduct) (AT\&T, T-Mobile, Verizon). If a message sender is observed sending any disallowed content, including sending unsolicited messages, phishing, or filter evasion, we will suspend your MESA account immediately.

All messages must comply with the opt-in requirements outlined in the [CTIA guidelines](https://api.ctia.org/wp-content/uploads/2019/07/190719-CTIA-Messaging-Principles-and-Best-Practices-FINAL.pdf). In short, businesses should send messages to customers only after receiving opt-in permission. Also, message senders should not use opt-in lists that have been rented, sold, or shared.

## Technical Notes

* The SMS tool only supports sending messages to the United States and Canada.
* The message body has a maximum length of 160 characters (after variable replacements have been made). If your message is longer than 160 characters, the task will be marked as Fail and no message will be sent.
* To avoid these obstacles, consider using the Twilio app, which has fees per message sent and requires additional configuration.


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