> For the complete documentation index, see [llms.txt](https://docs.voipnumber.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.voipnumber.net/how-to/voicemail-trunk.md).

# Voicemail Trunk

## Overview

Default [Voicemail with audio transcription](/features/voicemail-with-audio-transcription.md) is linked to a [Connection](/components/connection.md). This means it is reached when `SIP To` header has a value of that Connection's `SIP User`

<figure><img src="/files/0niiQ7UKJohauJvEL7ni" alt=""><figcaption></figcaption></figure>

Although you can send other Connections to the same voicemail by simply configuring a Call Flow on them, you may prefer to have a dedicated SIP URI that accepts *any* `SIP To` value (SIP user), even those without a corresponding Connection

With elastic SIP Trunking you can create a shared voicemail

<figure><img src="/files/DbrR1hEwApSYTJwiFs0e" alt=""><figcaption></figcaption></figure>

## Use Case

Send call with any `SIP To` header to single, shared voicemail

## Setup

1. Create a Call Flow with `Voicemail deposit` [action](https://docs.voipnumber.net/tools-and-features/call-flow-builder#action-voicemail-deposit) (see [Voicemail box](/how-to/voicemail-box.md))
2. Create a Trunk. Select a name and SIP URI (see [Trunk](/components/trunk.md)) for `SIP` input type (you can enable `PSTN` input too and you can also keep it `PSTN`-only but that can't multiplex SIP users)

<figure><img src="/files/8QK7B4iSqb6aBO0ATM8w" alt=""><figcaption></figcaption></figure>

3. Attach your Call Flow from Step 1 (see [Trunk](/components/trunk.md))

<figure><img src="/files/Wq9nJ0o3I2usKpuSpmcX" alt=""><figcaption></figcaption></figure>

You will likely leave `Trunk OUT` section of your Trunk disabled. In some more specialised scenarios you may enable it to send call further: to PSTN, mobile number or to another SIP URI

✅  You now have created a SIP Trunk with a flow that will accept call with any `SIP To` header and send them all to voicemail

<figure><img src="/files/0un3yXEdqr1iEGL4NqKZ" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/JpR4a4HFu8MBLDXIXlT8" alt=""><figcaption></figcaption></figure>


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