This is an endorsement to personal liability insurance and covers the cost of repair to a borrowed car (if the car in question does not have full casco insurance) as well as any potential loss of bonus applicable to your motor vehicle insurance. It only applies if the vehicle is occasionally (not regularly!) borrowed by friends or relatives. Occasional driving means, for instance, once a year for no more than 14 consecutive days. Some insurance companies require a sum insured of 5 million francs for this additional cover.
Note: This cover for occasional use of third-party vehicles is part of personal liability insurance, not car insurance.
In the home contents insurance comparison, you can select “Driving third-party vehicles” as an endorsement to personal liability insurance.
Example of cover for driving third-party vehicles:
You are driving a friend’s vehicle and run into the back of a car in slow-moving traffic. Both vehicles suffer damage to the bodywork. Because the friend's car is covered under personal liability insurance (compulsory), you don't need to worry about the damage to the car in front, as the insurance will pay for it. The damage to your friend's car, however, is not covered, unless your friend has taken out full casco insurance. However, under full casco insurance, there is a deductible of CHF 1,000, which you would have to pay in this case, unless you had added “driving third-party vehicles” to your policy.