If you are not 100% responsible for the accident and if there is contributory negligence then it is the responsibility of the insurer to calculate the amount of damage and take a decision as regards the liability. The excess amount that you are obliged to pay will be calculated according to your agreed policy and if you pay the excess first and once we have fully investigated the matter and found that you are not at fault we will refund you the excess. You should check your policy wording for more information particularly the sections on when an excess applies and when an excess does not apply.