> For the complete documentation index, see [llms.txt](https://help.sipgate.de/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.sipgate.de/cloud-telefonanlage/en/using-sipgate/mobilfunk/was-ist-der-mobile-zusatzanschluss.md).

# What is the mobile additional line?

There are situations in which it is enough to equip individual people or even devices with mobile service, without you having to book or create new users for them in the phone system. This is possible with the feature **mobile additional line** possible.

This way, you can, for example, provide employees who want to be reachable on the go and who can also make calls and use mobile data. Alternatively, devices such as surveillance cameras, alarm systems, and card readers are easily equipped with mobile service via the mobile additional line. And then several employees can access them independently of one another.

With the mobile additional line, unlike with newly created users, **not** the full range of the sipgate phone system can be used. For example, **no voicemail or event list** available.

## Where can I find the feature?

The starting point for user-independent mobile service is the [**mobile service tile**](https://app.sipgate.com/mobile-telephony) in the **account management**. Here you click on **book mobile service options**.

![sipgate-Hilfecenter-Mobilfunk3.png](/files/9ed1d1db74d099141ef699bb1495518a5427b9f5)\
Next, in the next step, choose **mobile additional line**.

After you have assigned the **device name** you just add a phone number.

{% hint style="warning" %}
**Important:** Please note that for this feature **only mobile numbers** can be used. Landline numbers are not available for this feature.
{% endhint %}

If your **Sender number** is supposed to be the same as the previously added phone number, you must enter it in the **device settings** of the corresponding **device card** manually.

![sipgate-help-center-mobile-service5.png](/files/4622fe472ef696d5c7c8bfd167d110593b3e912e)


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