> For the complete documentation index, see [llms.txt](https://guides.clickatell.com/sms-channel/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://guides.clickatell.com/sms-channel/getting-started/quick-start-guide-sms.md).

# Quick start guide (SMS)

To use Clickatell's SMS channel, you need to:

1. [Activate SMS](/sms-channel/getting-started/activate-sms-self-serve.md) as a channel in your account. *(self-serve only)*
2. Add a [new SMS setup](/sms-channel/getting-started/add-new-sms-setups-self-serve.md). *(self-serve only)*
   * As part of this step, you must purchase a [short code/long number](/sms-channel/getting-started/add-and-edit-sms-numbers.md). 
3. Start sending messages:
   1. Via Clickatell's [One API](https://docs.clickatell.com/channels/one-api/one-api-reference/)  or [HTTP API](https://docs.clickatell.com/channels/sms-channels/sms-api-reference/) to send and receive messages directly via SMS.
   2. Via Clickatell's [Chat Flow](https://clickatell.gitbook.io/flow/) and [Chat Desk](https://clickatell.gitbook.io/chat-desk/overview/overview) applications *(*[*Interact* ](https://www.clickatell.com/products/interact/)*or* [*Transact*](https://www.clickatell.com/transact/) *only)*.
   3. You can also use SMS with our Broadcast Messenger tool.

{% hint style="warning" %}
If you plan on using a **US Long Number**, please refer to the [10DLC](/sms-channel/10dlc-regulations-us/what-is-10dlc.md) section of this guide.
{% endhint %}


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