An offset mortgage allows you to use your savings to reduce the amount of interest you pay on your outstanding mortgage balance. It links your savings, and in some cases your current account, to your mortgage.
This means that instead of earning interest on your savings, you pay less interest on your mortgage. So, for example, if you have a mortgage of £125,000 and you have £25,000 in your linked accounts, then your monthly mortgage interest would be calculated on £100,000 instead of the balance of £125,000.
Whilst an offset mortgage can save you money and shorten your mortgage term, they can be more expensive than comparable deals, and there may be less choice available.
As a mortgage is secured against your home, it could be repossessed if you do not keep up the mortgage repayments.