IELTS required score varies from college to college, so we cannot simply make a statement that a particular country requires this much band.  I visited the sites of some of the colleges and universities in England, and I came to the conclusion that most of them were accepting IELTS band of 5.5. So, if you are able to score a 5.5 band then a there is a high chance that you might get admission in a college in UK given that the other requirements are filled.