In New Jersey there is not a minimum age requirement for obtaining auto insurance if you have your license or permit. However if you are under 18 and thus a minor you will normally need a parent or guardian to sign with you on any insurance paperwork since it is a legal binding document.
According to the NJ Department of Banking and Insurance (DOBI), which is the insurance regulatory body, if you are a teenager it will most likely cost less for you as a young driver to be added to your parents’ policy than to purchase your own. However, any driver with a car titled and registered in their name can purchase insurance.