# Integrate Voice in Frontline

> \[!WARNING]
>
> Voice Calling in Frontline will follow the same routing logic used for Messaging. Make sure to first configure [Inbound Routing](/docs/frontline/handle-incoming-conversations#inbound-routing) and your [Outgoing Conversation Callback URL](/docs/frontline/outgoing-conversations).

The Voice in Frontline integration will allow you to make and receive voice calls to and from your customers, all from the Frontline mobile application. In order to integrate the voice feature, you will need a Twilio phone number with voice capabilities. You will also need to make some configuration changes in the Twilio Console to get up and running with making voice calls. Let's get started!

## Verify you have a Voice-enabled Twilio Number

To check if your Frontline number is voice enabled, navigate to **Phone Numbers** > **Manage** >**[Active Numbers](https://console.twilio.com/us1/develop/phone-numbers/manage/active?frameUrl=%2Fconsole%2Fphone-numbers%2Fincoming%3Fx-target-region%3Dus1)** in the Twilio Console.

Each active phone number includes details on its capabilities. Verify that your Frontline number has the **Voice** icon, which means it is voice-enabled. If it does, you can skip down to the [Enable Voice in Frontline section below](#enable-voice-in-frontline) to continue Voice feature integration!

![Dashboard showing active phone numbers with voice capability filter applied.](https://docs-resources.prod.twilio.com/eee80d4c474f99887efa770fe5c711f45856104746f01402ad9a755bd972a3e2.png)

Otherwise, you'll need to purchase a voice-capable phone number.

### Buy a Voice-enabled Twilio Number

To purchase a number with Voice functionality, navigate to the [Buy a Number](https://www.twilio.com/console/phone-numbers/search) page in the console, check the **Voice** box and click **Search**.

![Interface for buying a number with options for country, capabilities, and search criteria.](https://docs-resources.prod.twilio.com/ff99cbdcbf9a79d8bb484ea70790857b28bddcf3c43f15e01d1d73bb90266273.png)

You'll see a list of available phone numbers and their capabilities. Find a number that you like and click **Buy** to add it to your account.

![Table of local phone numbers with capabilities and buy options.](https://docs-resources.prod.twilio.com/dab15c43efcacab8bb5de6a95a2d3ca39c2e8c5b6bf9b266143e2b0df2989f54.png)

Now that you have a voice-enabled phone number, we're ready to enable Voice functionality in Frontline!

## Enable Voice in Frontline

There are two configuration steps you'll need to follow to enable Voice calling:

1. Select the **Enabled** radio button on the Frontline Voice calling Console page.
2. Connect the TwiML App to your Twilio phone number.

### Enable Voice Calling

Navigate to the [Frontline Console](https://console.twilio.com/us1/develop/frontline/overview?frameUrl=%2Fconsole%2Ffrontline%2Foverview%3Fx-target-region%3Dus1). Go to **Manage > Voice Calling** section and click the **Enabled** radio button.

![Voice calling settings with 'Enabled' option selected for managing inbound and outbound calls.](https://docs-resources.prod.twilio.com/4433fc513cfb608b4a44787ba73260a5b90ad0591c0c13d42cf07fd77eb244d0.png)

Click the **Save** button.

Once the **Enabled** option is selected, the following will occur:

* A [TwiML](/docs/voice/twiml) App named **Voice in Frontline** will be generated. You will later configure your voice capable phone number to use this TwiML App to handle calls. This TwiML App will act similarly to a [webhook](/docs/glossary/what-is-a-webhook), and handle incoming and outgoing voice calls for your Frontline service.
* You will see the **Voice calling enabled** notification in the upper right-hand corner of your console window, signifying that Voice calling is now enabled for your Frontline application.

Next, we will assign the voice capable phone number we purchased earlier to the newly generated TwiML App.

### Connect a Phone Number to a Frontline TwiML App

You will need to tell Twilio to look to this newly-created TwiML App for instructions for any incoming or outgoing calls to your Twilio phone number.

1. In the Console, navigate to **Phone Numbers > Manage > Active Numbers**
2. Click on the phone number you purchased to use with Frontline. Scroll down to the **Voice & Fax** section
3. In the **Configure With** dropdown, select **TwiML App**
4. In the **TwiML App** dropdown, select the **Voice in Frontline** TwiML App
5. Click the **Save** button

![Twilio interface showing configuration of phone number with TwiML App for Voice in Frontline.](https://docs-resources.prod.twilio.com/a2309debbd945697a927ac25637998c1cc7e3464f78fe138cc2bc18a4fcbadf0.png)

> \[!NOTE]
>
> If your Frontline TwiML App is associated with many Twilio phone numbers, this manual process likely won't be the best solution. For example, you could automate this process by writing a script using [Twilio's Phone Numbers REST API](/docs/phone-numbers/api/incomingphonenumber-resource).

Frontline workers will now be able to receive incoming voice calls and make outgoing voice calls.

## Disable Voice in Frontline

To disable Voice calling functionality from your Frontline application, click the **Disabled** button on the [Voice Calling](https://console.twilio.com/us1/develop/frontline/manage/voice?frameUrl=%2Fconsole%2Ffrontline%2Fvoice%3Fx-target-region%3Dus1) console page and click the **Save** button.

![Voice calling disabled with instructions to remove incoming call handling.](https://docs-resources.prod.twilio.com/6ec663e29e63f55c4ccc2d7927a6d645055a5bcb914a303f3d5f4a039f24e5b1.png)

Once Voice calling is disabled:

* You will need to [remove any Frontline phone number configuration](#remove-frontline-voice-configuration) to block incoming voice calls to the Frontline application.
* You will see the **Voice calling disabled** notification in the upper right-hand corner of your console window, signifying that Voice calling is now disabled for your Frontline application.
* Workers in the Frontline app will no longer be able to place or receive new phone calls but will see records of any previously placed phone calls in their conversation history.

### Remove Frontline Voice Configuration

In the Console, navigate to **Phone Numbers > Manage > [Active Numbers](https://console.twilio.com/us1/develop/phone-numbers/manage/active?frameUrl=%2Fconsole%2Fphone-numbers%2Fincoming%3Fx-target-region%3Dus1)**. Once there, select the voice capable number you purchased earlier.

Scroll down to the **Voice & Fax** section. In the **Configure With** dropdown, select "**Webhook, TwiML Bin, Function, Studio Flow, Proxy Service**", as shown below.

![Dropdown showing configuration options for TwiML App with save button highlighted.](https://docs-resources.prod.twilio.com/0373183725b5c064328740ae7058995faa792045c9cbb629131a5884cba5b8bc.png)

Click the **Save** button. Now, the Voice configuration for a phone number is disabled.

You will see a notification message at the top of your console window, signifying that the number was successfully updated.

> \[!NOTE]
>
> If your Frontline TwiML App is associated with many Twilio phone numbers, this manual process likely won't be the best solution. For example, you could automate this process by writing a script using [Twilio's Phone Numbers REST API](/docs/phone-numbers/api/incomingphonenumber-resource).

## Mobile configuration

### Outgoing Calls

To make an outgoing call from an ongoing conversation with a customer, click the **blue phone icon** in the upper right-hand corner of the conversation screen.

![Chat interface with call icon highlighted for outgoing calls in Twilio Frontline.](https://docs-resources.prod.twilio.com/c8db79aa74e1e349442e0fdf5d3025f0d6b027bd8daa468c2b4884b6691d04ed.jpg)

You can also place a call from a particular customer's detail page. Navigate to a Customer Details page and under Contact details select the phone number that you want to call.

### Incoming Calls

When you receive an incoming call, you'll see a Frontline notification banner at the top of your mobile device. Click the **blue check icon** (iOS) or the green **answer** button (Android) to accept the call.

![Mobile screen showing Twilio Frontline incoming call from Ashley Johnson with recent messages list.](https://docs-resources.prod.twilio.com/75d197f0b58632d1726d60b317e690b7982198f1a53c7ed88a953c54a8e80310.jpg)

## Error Messages

You may see two types of error messages in the Voice calling Frontline Twilio Console:

* **Frontline Missing Phone Numbers**: You will see this error message if the Messaging service that is connected to the Frontline Conversation service doesn't have any assigned phone numbers in its Sender Pool.

  * To edit the Sender Pool in the Console:

    1. Click **Messaging > Services** in the left navigation.
    2. Click on **Default Conversations Service**.
    3. Then click **Sender Pool** in the left navigation pane.
* **Voice Calling Not Available**: If the TwiML app required to enable Voice calling on the Frontline application was updated or removed, you will need to [contact our support team](https://help.twilio.com/hc/en-us/articles/360048500694-Contacting-Twilio-Support)to restore Voice calling functionality.

## Advanced Voice Configuration

Would you like to customize Frontline's Voice behavior? Go to the [Advanced Voice Configuration page](/docs/frontline/advanced-voice-configuration) to learn how you can modify inbound and outbound call behavior in Frontline.