BT Mobile call forwarding and costs

[Ollie2222]

Thanks for the link. Interestingly it says

Calls to any other service will be charged at the standard rate for calls to that service. If these calls are available within any inclusive call package, they will be costed within it.

So as the BT mobile has unlimited UK national and mobile calls it should be free. I tried a few test calls from BT to another UK mobile operator in the UK and there are no charges shown on the itemised billing.

That said to avoid any possible problems I've just deactivated voicemail and will not accept any incoming calls or make any calls, text or use of data.

I've also set a sensible roaming cap on the account to stop anything going completely wrong.

[DonnyGuy]

So just to throw a spanner in the works...

I was a BT Mobile customer for all of five weeks a few years ago and the main reason(s) I left were due to the fact that whilst it worked perfectly and did everything it said on the tin in the UK (great UK calls, texts and data allowances), abroad it was rubbish. 

Firstly, if you roamed outside of the EU, you were looking at £5 per MB which means you hit your spend limit before you've left arrivals (even if you set it to the max) but secondly, because voicemail was a nightmare.

So I say to people when I'm abroad, usually people in the country I'm in "just call my UK number, I've deactivated voicemail, I won't answer and I'll call you back"

Cut to BT Mobile... automatically reactivating the voicemail diverts the minute you connect to ANY foreign network (so those instructions you set in the UK are no longer valid, you can deactivate the diverts on your home network but you have it whether you like it or not when abroad)

So people would call my UK number, I'd be in a bad signal area and they'd hear "Welcome to BT Mobile..." message and be charged for that international call to the UK. 

It took lots of back and forth at the time, as it's a strange problem statement to articulate until someone finally said "it's the way its been built unfortunately" so it's not going to be rectified (I should add BT Mobile business sims weren't affected as they were on a different platform to consumer, you cancelled voicemail on there, it stayed cancelled).

So the point of my story to the original poster is I did what you're suggesting to get round that situation when away. Diverted calls to another number. 

So if you divert all calls (using the **21*NUMBER# method) then so long as the number you are diverting to is part of your allowances, you won't be charged. As you're diverting ALL CALLS meaning your incoming calls will just divert immediately, the network won't even try to send the call to you on your roaming network. You're good to go. 

If you do opt to just cancel the voicemail, be aware that your calls will divert again as soon as you land. The good news though (and I laboured this point with them intensively) BT don't for those calls that ring and end up back in your UK voice mailbox. Just don't retrieve them until you're back in the UK as you would be charged to call 1571.

Other networks do charge if a call is routed to the foreign network and then back to voicemail. EE for example reference it on their roaming pages and tell you to de-activate voicemail so it rings out. Fair enough with them, you are in control.

Very long post I know but as this was my specialist subject way back when, I thought I'd share. 

[Ollie2222]

Thank you for your informative post, very helpful.

Like you I've been happy with the service in the UK and also in Europe when we've used it and as you say the cost of data roaming outside of the EU is just ridiculous at £5.70 per MB.

It's actually my other half who is travelling and with both SIMs in the phone with the non BT SIM set to be the one to be used when she landed she received a message from BT saying you've started using data outside of your allowance so will be charged.

No charges have appeared on the account so far (and there is a low cap anyway) but the decision was made to just use the other SIM and only turn the BT Mobile SIM on if she needed to receive an SMS.

As I had differing views on the cost of call forwarding we decided to switch it off but it sounds like it may well have worked.

As for voicemail when I next speak to her I'll get her to check if it's been activated again although if there's no charge to leave them on BT and as she's been told not to collect voicemails we should be good to go.

Am I right in thinking that you need to do any diversion while the phone is in the UK before travelling or does **21* work when abroad too?

Thank you for your advice, much appreciated.

[DonnyGuy]

If data roaming is turned off on the BT sim then you should be fine. It'll pick up the network abroad but not run up a bill. 

The **21*NUMBER# method will work abroad but it's only worth it if you need to receive incoming calls. If you're happy enough not answering them and them going to voicemail then you're all good. 

[GuiltyCol]

Great question Ollie, I'm having exact same issue and thoughts. 

I want to divert to another UK mobile that does allow international roaming to a country that BT Mobile does not.  Did you get it to work as you wanted in the end?

Currently I'm stuck on the first hurdle: just diverting my mobile to any other UK number using the **21*NUMBER# method isn't working.  I set it up, and no divert happens. No idea why not. 

I do get some message saying "invalid MMI code".   I tried this format: **21*+447123456789#  Is that right?

[GuiltyCol]

UPDATE: I can't seem to edit my post above, so replying to myself!

In case it helps anyone else: despite calling BT Mobile and being told forwarding to another mobile was impossible, I got the **21*NUMBER# method working.

I fixed the "invalid MMI code" by rebooting my phone into Safe Mode. I have a dual SIM phone and apparently getting an invalid MMI code error is a common problem. Safe mode fixed it.

Note also, it takes a minute or so for the redirection to work, so hang fire before testing it until you get a message saying it was successful.

[Ollie2222]

Hi,

Glad to hear you think you've got your problems sorted.

For me setting up the call divert wasn't an issue either via the call forwarding options on the phone or using the **21*NUMBER# method however as it was my other half who isn't the most techy and she was travelling through some more obscure countries to avoid any potential problem we decided to deactivate voicemail, not answer any calls and just call people back on the other sim.

If it had been me travelling then I'd have done a bit more testing.

Let us know how you get on.

[GuiltyCol]

Thanks Ollie, it all went fine whilst I was away, calls diverted to my Zoom landline number which rang on my phone via the Zoom app, perfect.

Except, when I got back home and cancelled the divert using #21# it took me a week to realise that nobody was leaving me voicemails. I called my own number and sure enough, voicemail wasn't working!

Well voicemail was turned on and active, but it seems #21# also cancelled the "Divert to voicemail if the call isn't answered after X seconds" delayed divert.  

I'll summarise my 20 minute call to BT Support in 1 sentence: to re-enable this, dial 15710 to turn voicemail OFF, then dial 15711 to turn voicemail back ON, and that resets the delayed divert; your custom voicemail message is not affected.