If my mum is insured to drive my car, does she still need insurance on her car?

Each car must be insured for it to be driven. Her policy covers her for driving someone else's insured car, but driving an uninsured car is a serious criminal offence and can result in loss of your license and serious fines. She can not cancel the insurance on her car and still drive it.

No you cannot go on her insurance to drive your car - its fraud, called fronting and is strictly illegal. Even if she was on your insurance as a named driver or illegally as the main driver it would not allow her to drive another car belonging to her. Named drivers on policies cannot ever be insured by that policy to drive any other cars at all. Unless she has a very special policy another car cannot be added to it at all. Even if she had this she could not add your car to it. You are looking for ways out of a high premium for yourself, understandably, but if you are going to own and/or be the main driver of a car then there is no way out.

Yes and No. Your mother has insurance for car ONE she can add car TWO to her policy if she wants. She as you say is insured to drive other cars. She cannot cancel her insurance and drive other cars. You can be added to her policy to drive car ONE and or car TWO. Whatever combination you like. There will be a NEW price on whatever arrangement you chose. It is not complicated to do and the price does vary depending on what you want to do. YOU ARE CHANGING YOUR INSURANCE COVERAGE you need a new(amended) policy to cover the change in you situation. This comes with a NEW QUOTE

Where to start with this question? You can't insure YOUR car in your MUM'S name - it, as others have said, is fraud. Your mother's policy states that she can drive other cars - so if YOU insure YOUR car in YOUR name, then yes, she can drive it according to the terms of her insurance. If she reads the terms of her cover to drive other vehicles, it will tell her that the other vehicle MUST NOT be owned by, or registered to, her & the other vehicle MUST have it's own insurance cover in place. So each car must be insured in it's own right - hers by her in her name & yours by you in your name.

Your mother's comprehensive insurance only applies providing that she keeps it in force for her own car. If she cancels that insurance then she will not be insured to drive anything unless it has its own policy in force. The "drive any car" part means that she can drive someone else's car PROVIDING that the person has insured the car in its own right. Your mother's insurance will be limited to "Third Party Only" cover when she is driving the other car. This may not be obvious just by looking at the insurance certificate but it will be somewhere in the small print of the Policy Document itself. Your mother can only cover more than one car under her policy IF her insurance company has a "Mulitcar" facility. Very few motor insurance companys will do this at the moment. Do not assume that her company will enable her to add your car to her policy. This is something that you will have to check with the insurance company directly. If you take out comprehensive insurance for your own car and have your mother as a "named driver" then she will be able to drive it and keep the full protection of comprehensive insurance. But she would not be able to drive her own car under these conditions because it would be uninsured.