All insurers generally require you to pay an excess when you make a claim. This is a specified amount that you'll need to pay upfront towards the costs of a claim.
With NAB, you'll pay a basic excess as outlined by NAB and a voluntary excess which you can choose to help lower the cost of your premiums.
In some cases, NAB may impose an additional compulsory excess depending on your claims history and risk. This will be outlined on your policy schedule or PDS.
There is also generally an earthquake and tsunami excess. This is an additional excess of $250 you'll need to pay for any claims related to an earthquake or tsunami, during any period of 48 consecutive hours.