BT Versatility: diverting calls externally and presenting a different number

BethM — Mon, 03 Aug 2026 14:28:31 GMT

The BT Versatility phone system is no longer supported by BT Business. Support ended on 30 September 2025, and we won't update this page if anything changes with the product.

If you're looking for a replacement system, check out all our cloud-based phone systems

We've brought our BT Versatility diverting help together in one post. It covers diverting incoming calls to outside numbers and presenting a different number on outgoing calls.

Diverting an incoming call to an outside number

The divert facility lets you divert calls to external numbers in the same way as to other extensions. Analogue lines must be configured as guarded clear lines on the system to allow external divert — if unsure, ask your network provider.

By default, external diversion is restricted for all extensions. This can be changed in system programming. See our BT Versatility system programming post. Unless an extension is allowed 'All calls' or 'External calls only', it can't set up call diversion to external numbers.

By default, to divert calls externally the system calls the external divert number and connects it with the original call through the system - the original call occupies one line and the call to the external number occupies a second line.

See page 86 of the Owner’s Manual for further details.

Presenting a different number on outgoing calls on ISDN2 lines

Your BT Versatility system can't change the phone number you show on outgoing calls. This was handled on the line instead, through BT's Presentation Number (PN) Digital Select Service, which let you show a different number as your Caller ID.

The person you called saw that number on their caller display, or when they dialled 1471 — so their return call came back to it.

Businesses mostly used it to steer return calls to the right place, like a central help desk, or because they made outgoing calls on different lines from the ones customers rang in on.

If presenting a different number matters to your business, it's a standard feature on our cloud-based phone systems.

topic BT Versatility: diverting calls externally and presenting a different number in Phone system

BT Versatility: diverting calls externally and presenting a different number

Diverting an incoming call to an outside number

Presenting a different number on outgoing calls on ISDN2 lines