This guide will show you how to setup a Basic SIP Trunk on your  3CX Switchboard. 

Login to your 3CX Switchboard with your ADMIN credentials. Then go to SIP Trunks on the left column menu: 

Click on "Add SIP Trunk"

Select "Generic" SIP Trunk/VoIP Provider.

Then select "Generic SIP Trunk".

And if you have been provided with a Virtual number (DID) by Megacall, add this number as "Main Trunk No". If you don't have any number just add a number of 4 digits minimum (e.g: 1111): 

Now you will get a Form that you must fill out with the SIP Trunk credentials. 

Trunk Details 

Firstly I suggest you to change the SIP Trunk name. 

Add Megacall's Gateway. 

And define the Limit of Channels (simultaneous calls) 


By default Megacall setup the SIP Trunk authenticating your Switchboard IP, therefore you don't need to add the User ID nor either the Auth. Password as we are already authorising any calls received from your Switchboard IP. 

Route calls to 

Here you can set the Main Trunk No you typed at the beginning when creating the SIP Trunk to assigned it to a Group or an extension.

You can also define the SIP Trunk Office hours in case you wish to disable the calls out of hours through this SIP Trunk. 

Add Inbound DIDs:

Inside the SIP Trunk configuration, open  the tab "DIDs", in this section you can add all your Inbound numbers you bought from Megacall: 

(Numbers must always include the International prefix, do not add "00" or "+" in front for the country prefix). 


Still in the SIP Trunk configuration open the Tab "OPTIONS" and check the following options only: 


Go to the last Tab called "Outbound Parameters":

And make sure it matches the following values: 

Finally, once all the above is completed, press the OK button on the top of the page to save and apply the SIP Trunk configuration. 

Once this is completed, you are ready to open the Outbound Rules and add this SIP Trunk to your Dialplan: 

Should you have any questions or experience any issues please contact our Technical Support team at "" for further assistance.