What is the interest on early repayment?

If you make an over payment and pay a large chunk off your balance, then this will reduce the amount of interest dramatically the next month. This is because we add the interest on each month based on your balance. The lower you balance is - the less interest we add. (This is why towards the end of your loan when your balance is lower, the interest that's added each month is a lot less than it was at the beginning of the loan)