Martin Lewis reveals how simple change to renewing car insurance could save you hundreds of pounds The finance expert gave the advice on ITV's This Morning Martin Lewis shared a tip for renewing car insurance Sign up to our free newsletter for the top North Wales stories sent straight to your e-mail Invalid EmailSomething went wrong, please try again later. Sign up now! When you subscribe we will use the information you provide to send you these newsletters. Your information will be used in accordance with ourPrivacy Notice. Thank you for subscribingWe have more newslettersShow meSee ourprivacy notice Every driver in the UK should know a golden rule when it comes to car insurance, according to finance expert Martin Lewis.