Can you change your last name to that of your partner in your health insurance if you are not legally married in New Jersey?

The only two ways you can legally change your name and use it officially is with a marital status change (actually getting married or divorced), or to legally change your name, which is a lot of paperwork. You could get charged for fraud by using a false last name for health insurance purposes. You could also get into trouble for adding yourself to a partner's insurance if there are no domestic partner laws in place in your state. You MUST check into domestic partner laws before doing anything so you don't get hit with a really nasty lawsuit from the insurance company. If there are domestic partner laws you can take advantage of, there is absolutely no need to use a false name in the first place.