The term underinsured motorist coverage (UIM) refers to an additional protection to the insured in the event they are involved in an accident caused by a driver whose policy does not fully cover the resulting property damage or bodily injury.

It can help cover medical expenses, loss of income, pain and suffering, and other damages suffered by the insured and their passengers, as long as the compensations exceed the liability limits of the at-fault driver.

The specifics of underinsured motorist coverage may vary depending on the policy and jurisdiction. In some cases, this coverage may be mandatory by law, while in others it may be optional. Some policies may set maximum coverage limits and may require the payment of an additional premium for this extra protection.