You must show course fees for the first year plus living costs: £1,529 per month for study in London or £1,171 per month outside London, for a maximum of nine months. That gives £13,761 or £10,539 respectively for a full-length course, on top of any unpaid tuition. The money must be held for 28 consecutive days in a qualifying account, and the closing balance date must fall within 31 days of your visa application date. This 28-day rule is applied strictly and is the single most common technical reason UK student applications are refused — plan the calendar backwards from your intended application date, and do not move the money during the 28-day window.