An excess is the amount you have to pay towards a claim on your home insurance. There are two types – compulsory and voluntary.
Your insurer sets the compulsory excess: it varies depending on the type of policy you have.
The voluntary excess is controlled by you, so you can set the amount you pay on top of your compulsory excess when you claim.
So, if your compulsory excess is £100 and your voluntary excess is £50, you'll have to pay £150 to your insurer towards the cost of your claim.
If you choose to pay a higher voluntary excess, you'll pay less for your insurance. Just make sure you don't set it so high you can't afford to make a claim.