transfer balance from one O2 sim to another?

[Anonymous]

I'm about to buy a new phone. I'm going for one of the cheapest I can get, because I rarely use my phone. I am currently on O2 pay as you go, text & web. I might get my phone from a chain shop (carphone warehouse, phones4u, that type of place) because although the cost works out about the same as getting it from an O2 shop/online, £10 of that is top-up. However, when I went and asked last week, I was told that you need to get a new sim, and the credit has to be put on that. However, I want to keep my old number. Can I either (a) transfer the £10 credit I get with the new phone to my old sim, or (b) use up the credit remaining on my current sim and then get my number transferred to the new sim I will get with my phone. Or should I be cheeky and go to the O2 shop, explain the situation and see if they will chuck in £10 credit if I get the asme phone from them?!

[perksie Level 69: Guiding Light]

Go and buy a phone, use the £10 credit, then as long as your old sim is still active you can transfer the number, or just put your old sim in the new phone and away you go.

[Anonymous]

If you buy from Carphone Warehouse or an O2 shop, you don't need to buy the extra top-up. Just tell them you are an existing customer. They will check your details and you might even be eligible for money off the phone.

[perksie Level 69: Guiding Light]

I didn't know you could do that, useful info thanks prking!