I believe the situation is in the United States, under 18, and covered on his parent's insurance policy. The up to 26 thing is voluntary. It used to be that if you turned 21 you could no longer be on your parents policy even if they did claim you as a dependent on taxes. Normally an employer policy would give you the option of single coverage, or family coverage, and you would have to pay in a certain amount each month. Presumably the policy could be changed but like you say that is probably unlikely as it would exclude the spouse too if you went to single only. If you are lucky and have a real good company they might offer a family policy at no cost to you and it would be dumb not to take it. So my sense is Idiot17 could use his card on his own and get therapy but what would his parents think if he did it without their knowledge and what would they do?