Interest is a payment due in exchange for the loan of money. The rate of interest
may be varied under the terms of most mortgage agreements.
Sometimes the interest will be calculated on the annual balance outstanding, which
is slightly different to the annual percentage rate. Ask your financial adviser
to explain how the various lending institutions quote the equivalent APR.
As interest rates change the amount due as the mortgage repayment may vary. Some lenders notify every borrower of every change – which can be an expensive process when rate changes are more frequent. Some have opted to make annual adjustments, or specify variable direct debiting as the only acceptable repayment method.