Who is responsible for an unlicensed driver driving another person vehicle involved in an accident?

The unlicensed driver is responsible for all damages. If they are a minor the parents may be forced to take responsibility.

Sadly, the owner of the vehicle MUST make any insurance claims they are eligible to make.

The owner can ask the unlicensed driver to pay any excess on the insurance and even take them to court if they refuse to pay it.

The driver of the vehicle is responsible to pay any amounts not covered by the vehicles owners insurance, including damages to the car.

If the insurance premium goes up or you loose your no claim bonus then I'm sorry but the driver is not liable for that.

If the unlicensed driver drove the vehicle without permission from the vehicle owner then the vehicle owner must report that the car was stolen at the time of the accident, then provide the insurance company with the police report number (you can tell the police you don't want to press charges). Under these circumstances even if the insurance company pays out damages for the vehicle they may chase the unlicensed driver to pay them back.