# How long may the phone numbers be that I use 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** (excluding the leading zero), otherwise accessibility, 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 entire dialed phone number (in **E.164 format**) in the **Request-URI** .

Further information can be found on the page 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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