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FRITZ!Box as SIP-Trunk PBX (from FRITZ!OS 06.50)

How to setup your FRITZ!Box (FRITZ!OS 06.51) with an easybell SIP Trunk

Manufacturer: AVM
Product name: FRITZ!Box 7490, 7390
Firmware: FRITZ!OS 06.51

We recommend you use the latest firmware version. You may find a newer version of this manual for models running the firmware 7.10 here.

Limits of the FRITZ!Box as a telephone system

A FRITZ! box can establish a maximum of 5 (older models) to 8 (newer models) SIP channels simultaneously. If you register an IP phone with the FRITZ! box, it also needs two channels for one call. We therefore recommend that the FRITZ!Box is only used as a telephone system for small companies with a maximum of 5 employees. For more information, please contact AVM.

For larger companies we recommend our Cloud Telefonanlage or one of the PBXs certified for our Trunk.

Please make sure, you’ve read our information about the form of phone numbers at incoming calls.


Setup in the easybell customer portal

Sign in your FRITZ!Box

  1. Please make sure your FRITZ!Box is connected to the internet and your computer.
  2. Please enter “” into the address bar of your browser. (If the FRITZ!Box is your IP-client, please enter the IP assigned by your DHCP server.)
  3. If you have got a password, please enter. Click “Anmelden” (sign in).

Setting up the telephony in the FRITZ!Box

  • Please click “Telefonie” (telephony) on the left side of the menu, now “Eigene Rufnummern” (own phone number), and “Neue Rufnummer” (new phone number).

F R I T Z S I P 1

  • Choose a connecting type (Anschlusstyp): “IP-basierter Anschluss” (IP based connection). Click “Weiter” (Next).

F R I T Z S I P 2

  • “Telefonie-Anbieter” (Provider): Choose “SIP-Anlagenanschluss” (SIP box connection).
  • Please enter your master number as your “Stammnummer” (master number) in the international format. In “Durchwahl der Zentrale” (number for headquarter), please enter the numbers which shall follow the master number. The “Interne Rufnummer in der FRITZ!Box” (internal phone numbers in the FRITZ!Box) is the complete phone number for the headquarter, but excluding the local prefix or the prefix of the country.
  • Now you can enter all your DID numbers. Therefore, please fill in the complete phone number in the international format in “Rufnummer für die Anmeldung” (phone number for registration) and the complete phone number without the local prefix and the prefix of the country in “Interne Rufnummer in der FRITZ!Box” (internal phone numbers in the FRITZ!Box). It should look like this:

F R I T Z Box Als S I P Trunk Telefonanlage 1


Registration information:

  • Benutzername (user name): your phone number (international format (eg. 0049+ Prefix without “0” + phone number)
  • Kennwort (password): your SIP password
    (You can find it in the customer portal: phone functions/settings)
  • Registrar:
  • Proxy-Server:

Format of phone numbers:

  • Landesvorwahl: none
  • Ortsvorwahl: none
  • Activate the option Eigene Rufnummer im internationalen Rufnummernformat übermitteln” (transfer own phone number in the international phone number format)

It should look like this:

F R I T Z Box Als S I P Trunk Telefonanlage 2



  • Rufnummerübermittlung: “Rufnummer im Displaynamen” (phone number on display name). Now you activated CLIP no screening. Now your complete number will be shown at outgoing calls. Therefore, you need to set up your phone functions in the customer portal (“phone functions” > “settings”): Mark “Geräte unabhänig” (independent from devices) at “Rufnummernanzeige” (display) and “From-Display (Standard)” at “Art der Rufnummernübertragung”.
  • Now please choose at “Paketgröße in Millisekunden” (package sized in miliseconds) “20”. If it looks like the following screenshot, please click “Weiter” (next).

F R I T Z Box Als S I P Trunk Telefonanlage 3

  • After the successful transfer of the IP-based telephony, please go back to “Eigene Rufnummern” (own phone numbers). Please click the icon for editing beneath the master number and fill in the actual DID number in the format of E.164. It should look like this:

F R I T Z Box Als S I P Trunk Telefonanlage 4

  • Click “OK” to save the configuration.