Underinsured motorist (UIM)
Coverage that may help when the at-fault driver’s limits are too low for your damages.
Plain definition
Underinsured motorist (UIM) coverage applies when another driver is at fault but their liability limits are exhausted or inadequate for your covered injuries or property damage, as defined in the policy. Some states combine UM and UIM; others separate them.
Why it matters
Minimum liability drivers may leave you with unpaid medical bills after their limits cap out. UIM is the gap filler when available.
Example
An at-fault driver carries $25,000 BI per person; your medical bills exceed that. UIM may pay additional covered amounts up to your UIM limits.
Common misunderstanding
UIM triggers only after the other party’s coverage is applied or tendered according to policy rules—not automatically on every large bill.
Policy language always controls. This is educational content, not advice. See our disclaimer.