What are Centrex lines?

Centrex lines are analog lines with additional functionality provided by the telephone carrier.

What features of Centrex lines does the PBX support?

Fonality supports the "Transfer and clear" setting if provided by the carrier.  This allows you to forward or transfer a call to an outside number without tying up two analog lines, one for the inbound call and one for the outbound call.

Transfer and clear will only work when used with the "Forward call to number" step in a call menu or with a blind transfer from a phone that has received the call directly - queues, FindMe, already transferred calls and the like will not allow us to transfer and clear the call, and so will require the use of two analog lines.

This feature is enabled in the Options --> settings page.

What changes do I need to make to use Centrex lines?

In many cases, no change is required. In some cases, the PBX must dial a 9 to dial outbound on Centrex lines.  If so, please change your Options --> dial plan dial strings to not strip the 9 from the call.