What does an uninsured driver pay when hitting an insured driver?

If it is the uninsured driver's fault in the accident, you can still file a lawsuit against the uninsured driver but you'll only be able to recover from their personal assets, which in many states won't be much because many states allow you to shield many personal assets from this sort of recovery.

You will also be filing a claim against your own Uninsured Motorist (UM) coverage on your insurance policy.