Regulations about adding a teenager to your auto insurance vary by state. In nine states -- North Carolina, West Virginia, Pennsylvania, New York, Ohio, Virginia, Illinois, Indiana and Maryland -- you must add your teen driver to your policy when they get their permit. In all other states, you may wait until your teen has his driver's license, or you may opt not to add him at all, letting him have a separate policy.
Amount of Driving
Many auto insurance policies extend at least a limited amount of your coverage to those to whom you lend your vehicle, because the insurance follows your vehicle, not the driver, as Insurance.com points out. If your teen isn't going to drive your vehicle much, you may be better off relying on the lending clause, as adding your teen formally may jack up your premiums. However, if your teen is going to be driving frequently, the insurance company will see that your insurable interest in your son is clear and likely will want you to add him.
His Own Policy
An alternative to putting your teen on your own insurance policy is to help them get an insurance policy of their own. This sometimes requires your teen to have a car of their own. This way, if your teen gets in an accident, the accident has no chance of raising your own insurance premiums. Ideally, your teen should pay for their policy on their own so he learns auto responsibility, but if your teen can't swing the premiums alone, you can give him what he needs to pay for the policy. You can help your teen save money on the premiums by getting him an older vehicle that isn't a sports model. Notedly, in general, it's cheaper to add your teen driver to your existing policy than it is to pay premiums for an additional policy.
The Bottom Line
To help determine whether to add your teen to your insurance policy, should contact the Department of Motor Vehicles or the Department of Insurance for your state. Your insurance agent also can advise you on when adding your teen is a good idea given your insurance company's specific regulations.