# Manage SIP Trunks

A SIP (Session Initiation Protocol) trunk is the connection that carries calls between your Cloud Voice phone system and your telephony provider (the outside telephone network). Once a trunk exists on your system, you can go back and change its settings at any time, or delete it when it is no longer in use. This page covers both tasks.

## Edit a SIP trunk

Edit a trunk when a setting needs to change: for example, updated credentials from your provider, a different codec, or new inbound or outbound routing behavior.

1. Sign in to the Cloud Voice management portal and open **Extension and Trunk > Trunk**.
2. Locate the trunk you want to change in the trunk list, then click the edit icon ![Edit](/images/pbx/edit.png) for that row.
3. Open whichever tab holds the setting you need and make your changes. Settings are grouped across several tabs, so the field you are looking for may not be on the first tab.
4. Click **Save**, then **Apply** to put the new configuration into effect.

:::note
**Save** stores your changes, but they do not take effect until you click **Apply**. If you leave the page after **Save** without clicking **Apply**, the trunk keeps running on its old configuration.
:::

:::caution
Many trunk settings (such as the registration credentials, host or server address, and port) must match exactly what your provider expects. A value that is correct on only one end will stop the trunk from registering and calls will fail. Confirm any changed values against the details your provider gave you before you click **Apply**.
:::

## Delete SIP trunks

Delete a trunk only when you are certain it is no longer carrying any calls.

:::danger
Deleting a trunk is permanent and cannot be undone. Any inbound or outbound calls that route over the trunk, including emergency (E911) calls, will immediately stop working once the trunk is removed. Before deleting, make sure no phone numbers, inbound routes, or outbound routes still depend on the trunk.
:::

1. Sign in to the Cloud Voice management portal and open **Extension and Trunk > Trunk**.
2. To remove a single trunk:
   1. Click the delete icon ![Delete](/images/pbx/delete.png) next to the trunk.
   2. Confirm by clicking **Yes** in the dialog that appears.
3. To remove several trunks at once:
   1. Tick the checkbox for each trunk you want to delete.
   2. Click **Delete**.
   3. Confirm by clicking **Yes** in the dialog that appears.

:::tip
Deleting several trunks with the multi-select method is faster than removing them one at a time, but check every ticked box before you confirm: the dialog deletes all selected trunks at once and does not list them individually.
:::