> 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/trunking/en/wie-lang-duerfen-die-rufnummern-sein-die-ich-fuer-sipgate-trunking-verwende.md).

# How long can the phone numbers be that I use for sipgate trunking?

Information on the maximum phone number length for sipgate trunking.

You can determine the length of your phone numbers with sipgate trunking yourself. However, for technical reasons, the length of the phone number should be limited to **a maximum of 11 digits** (without a leading zero), otherwise reachability, especially from abroad, cannot be guaranteed. For example, your phone number could look like this:

`01234 1234567`

The numbers should be entered exactly as they should be reachable. Incoming calls are signaled to your system with the full dialed number (in the **E.164 format**) in the **Request URI** signaled.

Further information can be found on the website of the [Federal Network Agency](https://www.bundesnetzagentur.de/DE/Fachthemen/Telekommunikation/Nummerierung/ONRufnr/Laenge/L%C3%A4nge_ONRufnr_Basepage.html).


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