A fixed mortgage rate plan is one wherein you will be required to make a payment of a fixed amount periodically towards the mortgage repayment. The interest rate and the repayment period are both fixed at the very beginning and this would also decide the amount to be paid periodically, where the period is usually set as a month. These however tend to have a higher rate of interest and this almost always implies that repayment period would be much longer when compared to other mortgage plans.

An offset mortgage is one where your savings account and the mortgage are combined into one and this would imply that whatever deposits that you make into your savings account can be considered as over payments towards the mortgage.

These are usually available with both fixed and variable interest rates. Though the mortgage interest rates might not be considerably lower compared to fixed rate plans, you will be able to save money on the long run as the credit balance on the mortgage will not be a static amount and will constantly be reducing with every overpayment which is made into your savings account.