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All you want to do is click thru to the deal you like and area your order. you will want to join up both online or over the smartphone, and there may be no want to worry approximately percent codes as your network will do maximum of the give you the results you want.
if you're upgrading to a deal on a unique handset however with the equal community (e.g. shifting from an antique Nokia smartphone to a brand new iPhone however staying with O2) then there's a truthful danger that you will be given a brand new SIM card, as the vintage one may not in shape inside the new handset. Switching the number over is often a quite simple process and may also be completed on-line with some networks. Vodafone call it 'SIM swap'. The community sends a textual content for your vintage smartphone and you just verify the SIM serial numbers (SSN) of your new SIM (for your new phone) and antique SIM (to your old cellphone). you could find the serial numbers on the SIM playing cards themselves or on the card that the SIM became at the start connected to. The community then does the relaxation, and it takes about half-hour for the switchover to appear. just make certain you back up your contacts before you turn.