# Allow Users to Monitor a Call by Dialing a Feature Code

When your team works from desk phones rather than an app, you can let trusted staff supervise live calls without any extra software. Set a feature code for each monitoring mode, grant the right extensions permission to use it, and those users can join an active call simply by dialing the code from their handset.

:::note
A feature code is a short dialing sequence (usually starting with `*`) that you key in on a phone to trigger a built-in PBX function instead of placing a normal call. Here it tells Cloud Voice that the caller wants to monitor another extension.
:::

## How monitoring permissions work

Out of the box, no extension can monitor another extension's conversation with a feature code, yet every extension remains eligible to be monitored. To hand monitoring rights to particular people, complete the steps below.

If instead you need to shield certain extensions so their calls can never be listened to, see [Disallow Users to be Monitored by Others](/pbx/administrator-guide/disallow-users-to-be-monitored-by-others/).

:::caution
Listening in on live calls is regulated in many regions and often requires that participants be notified or give consent. Confirm what your local laws and your organization's policy require before you grant monitoring rights, and only enable it for staff who genuinely need it.
:::

## Set up call monitoring feature codes

1. Sign in to the Cloud Voice management portal and open **Call Features > Feature Code**.
2. Find the **Call Monitoring** section. Here you choose which modes to enable, set their codes, and pick who may use them.

   ![Call Monitoring settings showing the Listen, Whisper, and Barge-in modes with feature codes and permission lists](/images/pbx/set-up-call-monitoring.png)

   a. Tick the checkbox for each monitoring mode you want to offer, then enter or accept its feature code:

      - **Listen**: Hear a live call without being audible to either party. Default code: `*51`.
      - **Whisper**: Hear a live call and speak only to the extension you are monitoring (for example, to coach an agent). The other party on the call does not hear you. Default code: `*52`.
      - **Barge-in**: Hear a live call and speak to both parties at once. Default code: `*53`.

   b. Use the **Listen / Whisper / Barge-in Permission** drop-down for each enabled mode to select the extensions allowed to use it.
3. Click **Save**, then **Apply**.

:::tip
Permission is granted per mode, so a user you add to the **Listen** list cannot whisper or barge in unless you also add them to those lists. Grant only the modes each person actually needs.
:::

## Result

An authorized user monitors a call by dialing the **feature code followed by the target extension number** on their phone.

:::caution
Keep these limits in mind:

- Conference calls cannot be monitored with a feature code.
- Extensions that are hidden on Cloud Voice App clients cannot be monitored.
- On an internal call where one party permits monitoring and the other does not, the call stays private and cannot be monitored, even by an authorized user.
:::