BT FTTP Digital Voice Transfer to IDNet

Evening All,

I Currently have BT Full Fibre 1000/100, and digital voice!

I am signed up to transfer to IDNet for both the Fibre and VOIP service.

I have been given a transfer date for the internet of the 16th (tomorrow)

And a transfer Date for the Phone of the 28th.

IDNet are telling me to continue using the VOIP hardware i have until the phone number transfers almost 2 weeks after the internet.

My simple understanding of this is that it wouldn't be possible - i wouldn't be able to use the BT router when fibre swaps to IDNet and BT won't give out details to use digital voice elsewhere.

Is there a way to make this work?
I've been in contact with IDNet, in an email trail but they don't appear to be understanding my issue.

I don’t think it’s possible either as BT Digital Voice (the residential offering) is a ‘walled garden’ service. Access from another ISP connection/service is not possible.

I guess you will find out today when the broadband swaps over…

In reply to a post by Fletch79:

I've been in contact with IDNet, in an email trail but they don't appear to be understanding my issue.

Really concerning that the team at IDNet haven't been able to grasp the issue which is clear for everyone with a little knowledge to see.

If the OP wants to keep the phone number he should port the number to a VOIP provider such as Voipfone, A&A, or even Sipgate if they will take a new customer.

Porting a number can cause the associated broadband to be discontinued and I don't know what will happen if the associated broadband has already been transferred to another supplier (Idnet).

To connect to the Voip provider the OP could use the Gigaset N300 just for Dect phones (preferably Gigaset ones) or for wired phones the Cisco ATA 191 or the Grandstream 802.

The OP is stuck between the devil and the deep blue sea as the full fibre is migrating from BT to IDNet today.

In reply to a post by dect:

In reply to a post by Fletch79:

I've been in contact with IDNet, in an email trail but they don't appear to be understanding my issue.

Really concerning that the team at IDNet haven't been able to grasp the issue which is clear for everyone with a little knowledge to see.

There is some info on the Idnet forums. There may now also be an IDnet VOIP service. If so it might be worth check the monthly charge and call costs.

Seems to me like the OP knew what they were letting themselves in for though....

Just IDnet being clueless.

If they had quoted me 16th for FTTP and 28th for VOIP I would have told them to get stuffed.

Not ideal, but can you get the BT App up and running on your phone? At least that way you should have some connectivity.

Consumer/Retail may be different, but I understood that BTs Business DV woud work on any ISP, although not proven. Consumer may be restricted to just BT FTTP lines.


It is a hurdle that no one seems to have a concrete answer to. I am looking to move a PlusNet FTTC to Full Fibre - they have agreed that the number can be released to a third party. However, nothing on the migration can be done until FTTP is installed, meaning a wait of a few days for the migration to be initiated and pushed through.

In reply to a post by MHC:

Consumer/Retail may be different, but I understood that BTs Business DV woud work on any ISP, although not proven. Consumer may be restricted to just BT FTTP lines.

BT's consumer/residential Digital Voice will only work on BT's broadband.
It requires the BT Smart Hub and that won't work with other providers (might work with Plusnet/EE?).
The BT Smart Hub needs to have a PPP connection to BT for Digital Voice to work so even if the Hub worked with Plusnet/EE the Digital Voice would not.

That goes for FTTC/G.Fast also, not just FTTP.

Those who buy BT voice only in FTTP only areas get a BT smart hub 2 on a 0.5/0.5Mb/s connection.
Even that won't work with another provider.

As it stands it isn't possible to get landline from BT and broadband from someone else on FTTP, as you currently can on FTTC over PSTN.

It should be possible to have both on a 4 port ONT with BT on port 1 with the 0.5/0.5Mb broadband for voice tier and broadband from another provider on another port, but that's still technically Digital Voice running over the BT Broadband.

The BT app might allow the OP to divert calls during the wait for migration but I don't think you can use the app to receive calls, on residential at least.

Edited by j0hn83 (Wed 16-Nov-22 13:56:31)

Perhaps more seriously, there is also a risk that the phone number will be lost between the voice service being ceased by BT, and it being "ported" by IDNet (it isn't really being ported, because by that stage it will already be terminated)

If this matters to you, then stop the FTTP line migration *now*. Get IDNet to do a same day port of both data and voice: or much better, migrate the voice to a standalone VOIP provider, and you'll never have to deal with this problem again in the future.

Doing it this way has the opposite risk: you may be without FTTP service for a number of days, between the VOIP port-out (which could terminate the BT FTTP service) and IDNet reactivating the line.

I say "could" because BT *do* supply data-only FTTP as a service, so it's *possible* that porting out the phone number will leave the FTTP data running - but I wouldn't bet on it.

In reply to a post by Pheasant:

Seems to me like the OP knew what they were letting themselves in for though....

Just IDnet being clueless.

I knew there could be issues - I've had a good read online before committing!

I'm not going to put this wholly on IDNet - There comms has been much better than any mainstream company throughout!

After a quick phone call with them i had hardware shipped next day and i am up and running with a temporary number!

In reply to a post by dect:

If they had quoted me 16th for FTTP and 28th for VOIP I would have told them to get stuffed.

these were sent in two separate emails - given a good length of time apart - i assumed both FTTP and Phone would have transferred on the same day!

Thanks for the replies - In the end the FTTP transferred seamlessly and i have a working phone - I'm just waiting for the number to port over!

Had a similar problem about a year ago. There was no easy way to port my existing landline number but I needed to keep it for continuity of contact with several people as it was the only number they had. It was a bit convoluted, but there was way a with BT of porting my phone number to a VOIP provider and keep my Fibre connection. As has been said, if you terminate the phone number as a way of porting,, the whole account is terminated including the data connection and then the chances of keeping your original phone number are drastically diminished. So the only solution to secure retention of my existing landline number was to port my number to a VOIP provider (Sipgate) and then on the day of transfer, having been notified that the number had been ported and checked on my mobile by calling it, I re-signed with BT on a Data only deal. The old connection kept active for about a week and then stopped. I had made arrangements to use a temporary Internet connection at home using a Dlink SIM modem which kept us going until BT reconnected on the new contract. Not sure why it took 2 weeks to re-connect a working Data connection - there was no re-wiring or any work required to make the connection just exchange and billing switching. Anyway, the outcome was I retained my landline number with a degree of certainty I would keep the same number. It just seems to make a straightforward job very difficult rather than just port the number and keep the Data connect on a Broadband only deal. It certainly isn't cheaper on the Broadband only deal.

In reply to a post by Fletch79:

Thanks for the replies - In the end the FTTP transferred seamlessly and i have a working phone - I'm just waiting for the number to port over!

Did they manage to reclaim your original number in the end?