In NJ you MUST have commercial plates to have permanent advertisements that include a phone number or web address. Your name can be permanent, but the contact info must be removable (magnets).



On the opposite end, if you have commercial plates, a contact number or website MUST be permanently displayed on the vehicle

These are the actual laws, but every area in NJ enforces it differently. I only know because I do vinyl decals full time and I also had a buddy go to court for his van (he's a pro surfer and his sponsors gave him a van with a promotional wrap)