Uninsured motorist coverage: when it pays and how much you can recover
Uninsured motorist (UM) and underinsured motorist (UIM) coverage pays an injured driver when the at-fault driver has no insurance or insufficient limits. UM coverage is mandatory in 20 states and optional in the rest. This article explains stacking, the offset rule, and the recovery process.
Uninsured motorist coverage: when it pays and how much you can recover
Uninsured motorist (UM) and underinsured motorist (UIM) coverage pays an injured driver when the at-fault driver has no insurance or insufficient policy limits to cover the injury. UM coverage is mandatory in 20 U.S. states plus the District of Columbia and optional in the remaining 30. This article explains the policy mechanics, stacking rules, the offset issue, and the claim process.
Why UM and UIM coverage exist at all
Approximately 14 percent of U.S. drivers carry no auto liability insurance, according to the Insurance Research Council 2024 estimate, ranging from 6 percent in Maine and Wyoming to over 25 percent in Mississippi, Michigan, and Florida. Another 30 to 40 percent of drivers carry only the state-mandated minimum, often $25,000 per person and $50,000 per accident, well below the typical cost of a serious injury. UM coverage fills the gap when the at-fault driver cannot pay.
What UM covers vs UIM
| Coverage | Pays when | Typical limit |
|---|---|---|
| UM (uninsured motorist) | At-fault driver has no liability insurance, or is a hit-and-run driver who cannot be identified | Matches the policyholders own liability limit or as elected |
| UIM (underinsured motorist) | At-fault driver has liability insurance but the limit is exhausted before the injury claim is fully paid | Same as UM in most states |
Mandatory vs optional UM states
States that require UM coverage as a default
UM coverage is mandatory or default-included in: Connecticut, the District of Columbia, Illinois, Kansas, Maine, Maryland, Massachusetts, Minnesota, Missouri, Nebraska, New Hampshire, New York, North Carolina, North Dakota, Oregon, Rhode Island, South Carolina, South Dakota, Vermont, Virginia, West Virginia, and Wisconsin. Most of these states allow the policyholder to reject UM coverage in writing, but it is included unless rejected.
States where UM is optional
UM is optional and must be purchased separately in the remaining 28 states plus Puerto Rico. A driver who declined UM coverage and is then injured by an uninsured driver has no first-party coverage source for the injury and must look to health insurance, Medicare, or out-of-pocket payment.
UM coverage limits and stacking
UM coverage limits typically match the policyholders own liability limit (the "matching" requirement) up to a state-defined ceiling. A driver with $100,000 per person liability coverage typically has $100,000 per person UM coverage by default. The policyholder can elect higher or lower UM limits subject to state rules.
What stacking means and where it is allowed
Stacking allows a claimant to combine UM coverage from multiple vehicles on the same policy or across multiple policies in the household. A household with three insured vehicles and $100,000 UM coverage per vehicle stacks to $300,000 of UM coverage available to any household member injured by an uninsured driver. Stacking is allowed in: Arizona, California, Georgia, Illinois, Indiana, Louisiana, Maryland, Massachusetts, Mississippi, Missouri, New Jersey, New Mexico, New York (limited), North Carolina, Ohio, Pennsylvania (limited), South Carolina, Texas, Virginia, Washington, West Virginia. Stacking is prohibited or limited in: Alabama, Arkansas, Colorado, Connecticut, Florida (anti-stacking statute), Idaho, Kentucky, Michigan, Minnesota, Nebraska, Nevada, New Hampshire, North Dakota, Oklahoma, Oregon, Rhode Island, South Dakota, Tennessee, Utah, Vermont, Wisconsin, Wyoming.
The UIM offset issue: gross vs net limits
UIM coverage compensates the gap between the at-fault drivers liability limit and the claimants damages. States divide on whether the offset is calculated against the at-fault drivers limit or against the actual settlement collected. Florida uses gross-limit offset: a $100,000 UIM policy reduces by the at-fault drivers $25,000 limit regardless of how much the claimant actually collects. Pennsylvania uses net-payment offset: the UIM policy reduces by the actual settlement amount. The difference can be a $25,000 swing on a single claim.
The claim process: notify your own insurer first
A claimant intending to file a UM or UIM claim should notify their own insurer in writing within 30 days of the accident, even if liability is still being investigated. Most policies require notice as a condition of coverage; late notice can defeat the claim. The notification should include the date and location of the accident, the at-fault drivers identity (or hit-and-run designation), and a description of the injuries. The insurer will assign a UM/UIM adjuster, who is a different person from the liability adjuster handling the third-party claim.
Settling the third-party claim before the UIM claim: the consent-to-settle rule
Most UIM policies require the claimant to obtain the UIM insurers consent before settling with the at-fault drivers liability insurer. Settling without consent can extinguish the UIM claim by destroying the UIM insurers subrogation right against the at-fault driver. The consent-to-settle clause is enforceable in nearly every state where the UIM insurer responds within a reasonable time, typically 30 days. An experienced personal injury attorney coordinates the timing so that the UIM claim is preserved.
Hit-and-run claims under UM coverage
Most UM policies cover hit-and-run accidents where the at-fault driver cannot be identified, treating the incident as if the at-fault driver were uninsured. Many states impose a physical-contact requirement: the at-fault vehicle must have actually struck the claimants vehicle, eliminating coverage for "phantom vehicle" near-miss claims where the claimant swerved to avoid an unidentified car. Florida, New York, and California have evolved away from strict physical-contact requirements; other states retain them.
Recovering against your own insurer is still adversarial
A claimant filing a UM or UIM claim against their own insurance company is in an adversarial position despite the first-party relationship. The insurer evaluates the claim with the same defenses it would raise against a third-party claim: comparative fault, prior medical conditions, mitigation of damages. The duty of good faith (see insurance bad-faith claims) constrains the insurers behavior but does not eliminate the adversarial element. A claimant should retain counsel for any UM or UIM claim above $25,000 in projected damages.
To find a personal injury attorney experienced in UM and UIM claims, use the directory at injury-lawyer.help. Browse California, Texas, Florida, New York, or any of the 50 states. For practice-area-specific listings see car accident attorneys.