# Getting started with an SMS Channel

This article details the steps required to set up an SMS channel for use with the Sinch Conversation API.

## Prerequisites

Before you can set up an SMS channel on the Conversation API, you need to do the following:

### General requirements

Note
If you have already completed the [Conversation API Getting started](/docs/conversation/getting-started) steps, you can skip this section.

1. Sign up for the [Sinch Build Dashboard](https://dashboard.sinch.com/).
2. Get access to the Conversation API.
3. Create your app.
4. Create your access key. Any API calls you make will require authentication information provided by your access key.


Refer to the [Conversation API Getting started](/docs/conversation/getting-started) section for more information on any of these steps.

### SMS Requirements

You must ensure that you have at least one service plan associated with your Sinch account. You must also have a virtual number assigned to that service plan.

Note
Each Sinch account is provided one service plan upon creation. Additionally, one test number is available for new Sinch accounts.

For more information on creating an SMS service account, see [How do I create an SMS service plan?](https://community.sinch.com/t5/SMS/How-do-I-create-an-SMS-service-plan/ta-p/8400). For more information on assigning a virtual number to an SMS service account, see [How do I assign a virtual number to an SMS service plan?](https://community.sinch.com/t5/SMS/How-do-I-assign-a-virtual-number-to-an-SMS-service-plan/ta-p/8421).

Warning:
The Conversation API is regional.
Your Conversation API App must be created in the same region that your service plan is provisioned. If your Conversation API App is created in a different region than the service plan is provisioned, the SMS channel will report errors.

## Configuring the Conversation API and SMS integration

After ensuring that you meet the above prerequisites,
you must enable the SMS integration for your Conversation API **app**.
You can do so using the [Sinch Build Dashboard](https://dashboard.sinch.com/convapi/overview), or using the API.

### Enabling the SMS integration using the Sinch Build Dashboard

When enabling the SMS channel
through the [Sinch Build Dashboard](https://dashboard.sinch.com/convapi/overview), select your **app** and click SET UP CHANNEL next to the relevant SMS channel.
Then, select your configured service plan from the drop-down box and confirm the integration.

You must also configure at least one Conversation API webhook which will trigger `POST` callbacks to the given URL. For more information on how to do this using the Sinch Build Dashboard, see [How to add a webhook to a Conversation API app](https://community.sinch.com/t5/Conversation-API/How-to-add-a-webhook-to-a-Conversation-API-app/ta-p/8100).

### Enabling the SMS integration using the API

To setup the SMS integration programmatically, use the following snippet to configure the channel
credentials for the **app** with the SMS channel:

```json
{
  "channel_credentials": [
    {
      "channel": "SMS",
      "static_bearer": {
        "claimed_identity": "{{SERVICE_PLAN_ID}}",
        "token": "{{API_TOKEN}}"
      }
    }
  ]
}
```

Replace {{SERVICE_PLAN_ID}} and {{API_TOKEN}} with your
Sinch SMS service plan ID and API token.

Note
Any API calls you make will require authentication information provided by your access key. For more information, see this [Overview](/docs/conversation/api-reference/conversation).

You must also configure at least one Conversation API webhook which will trigger `POST` callbacks to the callback URL. For more information on how to do this programmatically, click [here](/docs/conversation/callbacks).

## Next steps

After configuring the channel, you need to [set the channel priority](https://community.sinch.com/t5/Conversation-API/How-to-prioritize-your-channels-in-Conversation-API/ta-p/8613) in your app. Then, it's time to send your first message.

You must know your contact's `channel`/`identity` pair or `contact_id` prior to sending a message. For SMS, the `channel` is `SMS` and the `identity` is just the contact's phone number. To get a list of any existing `contact_id` values, you can make a GET request to the contact endpoint. For more information, see the [API reference](/docs/conversation/api-reference/conversation/contact/contact_listcontacts).

Important property!
If you are planning to send an SMS message using a free test number, make sure you understand the [SMS_SENDER](/docs/conversation/channel-support/sms/properties) property. You'll need to add it to your code and set it to your free test number.

br
If you already know how to set channel priority, or your channel priority is already established, you can use our [getting started guide](/docs/conversation/getting-started/) to begin sending and receiving messages.