I worked at a local gp surgery as a HCA and did new patient checks, one day an American girl can in for her check and I, being nosey,,,asked where she was from, how long had she been here, all the usual questions you ask when you meet a fellow american. Well, she wasn't too eager to answer my questions, very evasive and seemed a bit uncomfortable with me, so I suspected she was living here on a visitors visa. Anyway, I asked one of the doctor's about the rules of the PCT/NHS concerning non-UK citizens and she said it is left up to individual doctor's, nothing is set in stone. Some practices may charge a few, some might not, some may choose to register any and everybody. So, I think it is just up to the practice. Oh, and btw,,,that girl was only with the practice for a short while and she never would talk to me after that first encounter!