What bednobs says is no longer the case.
It used to be that all insurance companies applied this ridiculous rule, but some have broken ranks, applying the no claims to both cars.
I recently bought a new car (new to me, not new, new) – I rang my insurance company to advise of the date I planned to collect the car from the garage, with a view to changing over the insurance. In the past, in this situation, my insurance company has given me a 14 day change over period, during which both cars were insured.
I was advised by my insurance company to insure the new vehicle (with them), with full no claims discount. Once I sold my old car, that I should then cancel the insurance on the old car – my remaining premium would be refunded (based, pro-rata) less a £25 administration fee.
Effectively my insurance company were allowing me full no claims on a second vehicle, which no longer has to be earned.
My insurance company is ‘Direct Line’ – I’m sure that they are not the only company offering this insurance discount.