> 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/connections-and-integrations/asteriske/wie-setze-ich-meine-eigene-absenderrufnummer-in-einer-3cx-telefonanlage.md).

# How do I set my own caller ID in a 3CX phone system?

As a 3CX user in combination with sipgate trunking, you have the option of setting a **caller ID of your choice** for each extension.

The outgoing caller ID for the individual extensions can be set in a 3CX phone system as follows:

{% stepper %}
{% step %}
**Select extension**

First, select the extension to be configured in the 3CX system menu.
{% endstep %}

{% step %}
**Enter phone number**

Then go to **General ➔** **Outgoing caller ID**. Enter the desired number here in the **E.164 format** (49xxxxx / without a plus sign or leading zeros).
{% endstep %}
{% endstepper %}

{% hint style="info" %}
If the outgoing caller ID is not set here, then the called party will see the **Fallback caller ID number** that you can find in the logged-in area of your sipgate account under **Trunking** .
{% endhint %}


---

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