Wyoming's mandatory auto liability insurance law requires that anyone driving a motor vehicle must satisfy the state's financial responsibility limits of 25/50/20.

Under the Wyoming financial responsibility law, liability policy means an owner's or an operator's policy of liability insurance, certified as proof of financial responsibility, and issued by an insurance carrier authorized to transact business in this state, to or for the benefit of the person named as insured.

From this information it appears that anyone driving must have insurance on them as a driver. I would check with the Wyoming Department of Transportation to find out if this is correct according to Wyoming Motor Vehicle Statutes.

Also when your son is getting a license, since he is under 18, you as the parents will need to sign a minor's release form. Part of this form may include keeping insurance coverage or being responsible for the minor while he is driving so find out from the WY DOT exactly what the release form states.

Finally, most insurance companies will require you to list any household licensed drivers on your policy. Thus when your son gets his license you will need to inform your insurance provider and they likely will require you add your son to the policy at that point since with a license he is very likely to drive your vehicle and thus will need to be insured.