I have had a nightmare with mobiles.co.uk cash back, I had no problems the 1st & 2nd claim but on the 3rd & 4th claim mobiles.co.uk just ignored all emails and online claims. I contacted Carphone Warehouse but they refused to have any involvement and claimed although they owned Mobiles.co.uk they had their own procedure and nothing to do with CPW. But, all the cash back cheques are directly from CPW and are clearly marked CPW. I would advise do not use Mobiles.co.uk if you want cash back use another otherwise you are going to have a nightmare like me trying to get the cash back cheque. I am currently trying to get the 4th cheque at this moment and the will be trying again in 3 months to get the last cheque, they are just not worth the effort.