I'm thinking of buying a pay as you go phone from the O2 shop but already have an O2 sim I use.
If I buy a phone and it comes with a £5 bundle sim will I be charged the initial top-up fee of the sim or can I discard it, only paying the upfront cost of the phone.
I assume you mean online shop as all high street stores are closed?
If so, you just choose any tariff and they send you a sim corresponding to that tariff, but do not charge you for the tariff.
You would only pay if you chose to top up the sim, so just ignore the sim that comes with the device and use your own.
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