Part C: Uninsured & Underinsured Motorists

Key Takeaways

  • Part C UM/UIM is first-party coverage that responds when the at-fault driver has no insurance or not enough to pay the insured's injuries.
  • Uninsured motorist covers no-insurance, hit-and-run, and insolvent-insurer situations; underinsured motorist covers insufficient limits.
  • UM/UIM limits may not exceed the policy's bodily-injury liability limits.
  • UIM pays the difference between the insured's damages (up to the UIM limit) and amounts recovered from the at-fault driver, not stacked on top.
Last updated: June 2026

Part C: Protection Against Bad Drivers

Part C (Uninsured/Underinsured Motorists, UM/UIM) is a first-party coverage that steps in when the at-fault driver has no insurance or not enough insurance to pay the insured's injuries. It places the insured in roughly the position they would have occupied had the at-fault driver carried adequate liability coverage. Because Ohio is an at-fault state, UM/UIM is the insured's safety net against the many drivers carrying only minimum limits or none at all.

Uninsured vs. Underinsured

TypeTriggers when the at-fault driver
Uninsured Motorist (UM)Has no liability insurance, or is a hit-and-run/unidentified driver
Underinsured Motorist (UIM)Has liability limits lower than the insured's damages (and lower than the insured's UIM limit)

Uninsured motorist coverage applies when the other driver has no insurance, is a hit-and-run, or whose insurer is insolvent. Underinsured motorist coverage applies when the other driver has some insurance but not enough to cover the insured's damages; UIM typically pays the difference between the insured's UIM limit and the amount actually recovered from the at-fault driver, not stacked on top of it.

UM/UIM Limit Rules

A key rule the exam tests: the UM/UIM limits cannot exceed the policy's bodily injury liability limits. An insured who carries 100/300 liability can buy UM/UIM up to 100/300 but no higher, because UM/UIM is designed to restore the protection a responsible at-fault driver would have provided, not to create a windfall. Some states allow UM property damage (UMPD) as well as bodily injury; the bodily-injury form is the core tested coverage.

Worked UIM Example

Suppose an insured suffers $80,000 of bodily-injury damages in an accident caused by a driver who carries only Ohio's minimum $25,000 per-person BI limit. The insured carries $100,000 UIM. The insured first collects $25,000 from the at-fault driver's insurer. Because the insured's UIM limit ($100,000) exceeds that recovery, UIM responds for the difference up to the UIM limit: $100,000 UIM limit minus the $25,000 already received equals $75,000 from UIM, bringing the insured to $100,000 total, which here fully covers the $80,000 of damages.

This reduce-by-amounts-recovered structure, rather than adding the UIM limit on top of the at-fault recovery, is the calculation the exam expects.

Why It Matters in Ohio

Ohio law historically required insurers to offer UM/UIM coverage, and although a named insured may reject it in writing, the coverage is central to protecting Ohio drivers given the prevalence of minimum-limits and uninsured motorists. A scenario describing an at-fault driver with no insurance or with limits far below the victim's losses is signaling Part C, and the exam wants you to identify whether UM (no insurance/hit-and-run) or UIM (insufficient insurance) applies and to compute the reduced UIM payment.

Test Your Knowledge

An insured carries 100/300 bodily-injury liability limits. What is the maximum UM/UIM bodily-injury limit the insured may purchase?

A
B
C
D
Test Your Knowledge

An insured with $250,000 UIM is injured ($200,000 in damages) by a driver carrying only $25,000 in liability. After collecting the $25,000, how much does UIM pay?

A
B
C
D

Computing the UIM Shortfall

Part C protects the insured against drivers who carry no insurance or too little. Uninsured motorist applies when the at-fault driver has no insurance, is a hit-and-run or unidentified, or whose insurer is insolvent. Underinsured motorist applies when the at-fault driver has some insurance but not enough, and UIM pays the difference between the insured's damages (up to the UIM limit) and the amount recovered from the at-fault driver, not stacked on top of that recovery.

A worked UIM case: the insured suffers $90,000 in bodily-injury damages caused by a driver carrying Ohio's $25,000 minimum, and the insured holds $100,000 UIM. The insured collects $25,000 from the at-fault driver, then UIM pays up to its limit to cover the shortfall, here $65,000 ($90,000 damages minus the $25,000 recovered), bringing the insured to full recovery within the $100,000 UIM limit.

SituationCoverage
At-fault driver uninsuredUM
Hit-and-run/unidentifiedUM
At-fault driver underinsuredUIM (reduce-by-recovery)
UM/UIM limit capCannot exceed BI liability limits

Two rules are tested directly. First, UM/UIM limits may not exceed the policy's bodily-injury liability limits, because the coverage restores the protection a responsible at-fault driver would have provided, not a windfall. Second, Ohio insurers have historically been required to offer UM/UIM, which a named insured may reject in writing. When a scenario describes an at-fault driver with no insurance or with limits far below the victim's losses, identify UM (no insurance) versus UIM (insufficient) and compute the reduce-by-recovery payment.

Two UM/UIM rules are tested directly: the coverage cannot exceed the policy's bodily-injury liability limits, and UIM pays the shortfall between the insured's damages (up to the UIM limit) and amounts recovered from the at-fault driver, not stacked on top of that recovery. Identify UM (no insurance, hit-and-run, insolvent insurer) versus UIM (insufficient limits), then compute the reduce-by-recovery payment.

In Ohio's at-fault market, where many drivers carry only the 25/50/25 minimum or nothing, UM/UIM is the insured's safety net, and insurers must offer it though a named insured may reject it in writing.

A common UM/UIM trap offers an answer that adds the UIM limit on top of the at-fault recovery; the correct approach reduces by the amount recovered, paying the difference up to the UIM limit, so always subtract the at-fault driver's payment before applying the UIM limit, and never let the combined recovery exceed the insured's actual damages.