Why can't I have a duplicate sim card

[Alan5353]

I have an old phone that I use when it's too risky to have my main phone with me.

To do this I have to swap over my sim each time.

Why can't I have a second sim with the same number ?

I only want to have one phone active at any one time so what is the problem with EE offering this service ? 

[wardi]

Sorry Alan5353, my understanding is that 2 sims with the same number isn't possible, this seems to apply to all networks.  I'm not sure of the technical reasons behind this.

[James_B]

Hi @Alan5353,

Welcome to the EE Community. 🙂

@wardi is correct, I'm afraid it isn't possible to have two active SIM cards with the same number.

James

[Alan5353]

I don't want two cards to be active at the same time. Just one or the other.

It seems that providers can supply phones with two sims, 5G and esims but are unwilling to let customers have an option to use an old mobile when you don't want to risk damaging an £800+ phone.

I'm sure many customers would jump at the chance if this service was offered, even if a small charge was applied although it should be free.

People running, cycling, fishing, sailing, climbing even on a night out would rather pick up an old handset.

Is it in fact, providers just want to sell you another contract ?

[mikeliuk]

Hi @Alan5353 ,

I believe you are proposing that the service provider commits a criminal offence by producing a "duplicate sim card" for you.

It is an offence under https://www.legislation.gov.uk/ukpga/2002/31/section/1 (the device is the SIM).

The proposal is a variant of phone cloning: https://en.wikipedia.org/wiki/Phone_cloning

Edit: it is also a typical technique used by fraudsters: https://www.vanguardngr.com/2020/08/sim-card-cloning-fraud-now-in-vogue-bank-customers-warned/

Edit2: it also defeats two-factor authentication, as the assumption that only you have access to your physical device will be broken if you have left a cloned SIM somewhere else.

[Chris_B]

@Alan5353  The phones that can have 2 sims ( eSim ) are separate numbers from each other and each has their own allowance and tariff and can be on 2 different networks.  

[bristolian]

It is technically impossible to have 2 SIMs active on the same number.

In years gone by, VF & Orange offered "multi-SIM" facilities where two separate SIMs - each with their own subscription and number - could be linked in order for them to behave as if they were the same number. Both services had limitations (VF's couldn't use data on the multi-SIM, Orange's had some issues with SMS on the additional).

In any case, these services generally worked well, but have been withdrawn since many years and nothing similar is currently available.

[Alan5353]

Thanks for the help.

If that's the case then ill just keep swapping the sim over when required.

Will this cause problems ?

It is a shame that there isn't a solution. Phones carry so much personal data now that it's like taking a laptop with you everywhere you go.

That's not a problem normally but who would take a laptop on stag night ?

[Chris_B]

@Alan5353 as long as you’re careful with the Sim card you’ll be okay but Sim cards are not designed to be swapped from device to device on a regular basis so you could end up damaging the Sim card and then you need to request a replacement SIM card.  

[Alan5353]

Thanks for the help