Using a 4G watch with a different eSIM number to the phone

[Sparky8691]

Hi everyone. I imagine this a quite a niche and techy question. I currently have a Note 10+ and a Galaxy Watch 4G, planning on upgrading to a Galaxy Watch 3 soon.

My question is about the 4G functionality of the watch. When I first got the Galaxy Watch I was with the EE mobile network (I'm in the UK), EE do offer eSIMs for smartwatches where the watch shares the mobile number of the SIM that's being used in a comptabile phone handset. So this worked correctly for a year or so, with the watch working off Bluetooth when in range of the phone and then switching to standalone mode when out of range, where it would use the 4G connection from the eSIM.

Unfortunately I had some financial difficulties for a while last year and could no longer afford my EE phone bill, it had got up to £240 per month as I had a number of different devices on it. So EE closed my account, and I can't have a contract with EE again. I'm currently using devices I've purchased outright and a SIM only mobile contract with BT Mobile, who have accepted me as a contract customer however they do not offer eSIMs so my watch has been running with Bluetooth connection only since I've been with them.

The only other network that offers eSIMs that share the mobile number of the phone in the UK is Vodafone, like EE they only offer eSIMs to contract customers, NOT pay as you go for whatever reason. I did try applying for a Vodafone contract recently so I could get an eSIM with them but was turned down.

I have looked into other options and found a pay as you go eSIM provider: www.esim.net/uk they advertise comptability with Galaxy Watch 3, however if I purchased an eSIM from this company it would be a different mobile number to that of my phone. So I'm interested to know how this setup would work. The ideal of course, as I imagine is intended by Samsung, is that 4G watches share the number of the paired phone however this option appears to only be available in the UK to contract customers of EE and Vodafone, neither who will accept me as a customer as contracts require a credit check. I think this is silly, fair enough they can turn me down for a contract but they should offer that same service on a a pay as you go basis.

Back to the question - how would it work if the watch has a different mobile number on its eSIM? I imagine whilst within Bluetooth range of the phone it would function as normal. Out of Bluetooth range with the watch in standalone mode if I text or called anyone they would receive these from the watches different number. And if one of my contacts text or called me it would show up in my watch, but how would the watch indicate that it was to the watches different number, not my phone's number? Would it indicate it in the same way it shows how an existing contact in your phone might text to SIM 1 or SIM 2 if you were using the dual SIM functionality of the phone? The watch syncs message and call logs over Bluetooth whenever in range so it would need some way of indicating a message or call from a known contact has come from the phone sync or to the watches own 4G number.

There is also the 'Call and text on other devices' aspect to my query. As I understand it, 'Call and text on other devices' will route calls and texts from a registered device through my phone so contacts that I call or message will see my phones number even if the registered device is a WiFi only device or has a different mobile number? There is an option to 'Use mobile data' in the 'Call and text on other devices' settings so if I had a Galaxy Watch 3 and this was a registered device, even if the GW3's eSIM had a different mobile number as explained above, if it could connect to my phone using the mobile data connection of that eSIM it would effectively give me the same functionality as if the GW3 was sharing the phone's mobile number? So the only downside to this setup I can see compared to the carrier implemented sharing of the phone's number with the watch is if my phone was actually turned off or out of any mobile network range, the 'Call and text on other devices' function wouldn't be able connect to my phone and the watch would revert to calls and texts using its own mobile number. But as explained this appears to be the only option I may have to use the 4G functionality of the watch.

This post seems to confirm how this setup would work, by showing that the GW Active 2 can be a registered device in 'Call and text on other devices': https://www.reddit.com/r/GalaxyWatch/comments/dsj2xh/how_to_make_calls_on_galaxy_watch_active_2_over... in that post the OP is using that setup to do calls over WiFi on their GW Active 2 but if that works then the mobile data function should work too. Interestingly the original GW does not seem to support that so I'd have to wait til I get the GW3 I'm planning on upgrading to til I can do this.

[Mitzzz999]

when you had your EE phone contract and watch contract... there was always 2 different numbers... one for your phone and one for your esim in the watch.

[Sparky8691]

Yes I'm aware that EE actually register a different number for the watch's eSIM but when you do make a call or send a text using the watch in standalone 4G mode EE will make the call or text appear to come from the phone's number. The mobile number of EE's eSIM is used purely to access the carrier's network and associate the connection with the customer's account. Kind of like how using Google Pay creates a virtual card number for a payment card added to the wallet, so when contactless payments are made it doesn't expose the underlying card number, but in that scenario it's for security purposes whereas with the watch eSIM it's for convenience so only one mobile number is needed to manage texts and calls across two 4G devices.

I'm sure Samsung and the carriers, EE and Vodafone, have worked to integrate this system - so when the watch receives a call or text it knows to associate it with the paired phone's number. I won't be able to rely on this carrier integration if I can't get a contract with EE anymore or with Vodafone, and I use a seperate provider for the eSIM so I'll need to rely on the 'Call and text on other devices' feature to have things synced up under my phone's mobile number.

'Call and text on other devices', as far as I understand, only works if the phone is on and connected to a network, allowing the watch to connect to it and make calls and texts through the phone. So if say my phone runs out of battery and I use my watch for a call it would then be using its own number without any carrier integration or Samsung feature to use my phone's number to do that. I'm interested to know how that would work in practice and how the watch will differentiate between calls & texts synced using 'Call and text on other devices' or calls and texts made using its own number.

[Purloiner]

It seems with my GW3 I can only use 4g with the same mobile company that my phone is connected to, and only if that company supports GW3 esim.
I'm currently with Virgin mobile that don't support esim.

I'm thinking of changing to Vodafone Red sim only plan as the Red plan supports Vodafone One number.

O2 seem a bit of a daft setup with you needing to leave your mobile phone on and connected to data for the GW3 to work out of range.