Used to be the case, but they are trying to crack down on it due to too much fraud i guess, and well to sting us for even more money.

As said if your over 25, and have fully comp on your own vehicle, your insured on someone elses 3rd party.

(note that the 3rd party car must hold valid insurance buy the actual owner also!!)

As said check your policy, it used to be standard issue, but many have put an end to it!