There are ways around this. Insurers will advise what you have said, but I believe as you do that it is unfair to not be able to use your no claims on more than one policy. Insurers ask "do you have proof of your no claims history?". Providing this proof to more than one insurer is satisfying their requirement, as such it would not appear to be breaching any regulations or rules I am aware of. Insurers will have you believe differently, to prove this, some insurers will allow you to use these no claims on more than one vehicle, as long as you insure both cars through them. Esure and Admiral allow this as far as I am aware. I would contact a few insures or your current one and see if they will.