In this guide
Uninsured motorist (UM) coverage pays for your injuries, and in some states your car damage, when an at-fault driver has no insurance or flees the scene. Underinsured motorist (UIM) coverage steps in when the at-fault driver has insurance, but not enough to cover your losses. It protects you from other people's gaps in coverage, and about 14% of drivers were uninsured in 2022, according to the Insurance Research Council data reported by the Insurance Information Institute (Triple-I).
Key takeaways
- UM covers you when the at-fault driver is uninsured or a hit-and-run driver. UIM covers the shortfall when the at-fault driver's limits are too low.
- About 19 jurisdictions required UM coverage as of Triple-I's 2022 chart, but rules differ and some states let you decline in writing.
- Your own policy's limits set how much UM/UIM pays, so choose them with your own injuries in mind.
- Details such as property damage, deductibles, and how UIM is calculated vary by state and insurer.
- UM/UIM works alongside, not instead of, medical payments, PIP, and collision coverage.
The problem UM/UIM solves
Liability insurance pays for damage you cause to others. It does nothing for you if someone else causes the crash. If that driver has no insurance, or their limits are low, you could face medical bills and car repairs with no one paying them.
Triple-I, citing the Insurance Research Council, estimated that 14.0% of drivers, about one in seven, were uninsured in 2022. That figure is a ratio of uninsured motorist claims to bodily injury claim frequencies, so it is an estimate, and the share varies by state and year. The point is that meeting an uninsured driver is a real possibility, not a rarity.
Uninsured vs. underinsured: how each works
| Situation | Coverage that may respond | What it generally pays |
|---|---|---|
| At-fault driver has no insurance | Uninsured motorist (UM) | Your injury costs, and possibly property damage, up to your UM limits |
| Hit-and-run driver cannot be identified | UM, in many policies | Same as above, often with a requirement to report to police |
| At-fault driver is insured, but limits are too low | Underinsured motorist (UIM) | The shortfall between your losses and the other driver's coverage, up to your UIM limits |
| You are at fault | Neither | Liability, collision, and your other coverages apply instead |
The NAIC explains UM as paying you if an uninsured or hit-and-run driver hits you, and UIM as paying when an at-fault driver's insurance does not fully cover your losses.
A simple example
Suppose another driver runs a red light and injures you. Your medical bills and lost wages total $60,000, but the other driver's policy limit for one person is $25,000. If you have UIM coverage with enough limits, it may help cover part or all of the remaining amount. Exactly how UIM is calculated differs by state and policy, so read your policy language or ask your insurer.
What UM/UIM can pay for
Coverage details depend on the state and policy. Commonly, UM/UIM bodily injury pays for:
- medical and hospital bills not paid by other coverage,
- lost income if you cannot work,
- pain and suffering in many states, and
- funeral costs in a fatal accident.
Some states also offer uninsured motorist property damage coverage, which can pay for your car or belongings if an uninsured driver damages them. In other states, you rely on collision coverage and pay your deductible. Ask what your policy includes.
Good to know: UM/UIM generally applies to you, your family members listed on the policy, and passengers in your car. It may also follow you when you are a pedestrian or in someone else's car, depending on the policy.
Where UM/UIM is required
As of Triple-I's chart, dated October 25, 2022, these states required both UM and UIM: Connecticut, Illinois, Maine, Maryland, Minnesota, Nebraska, New Jersey, New York, North Carolina, North Dakota, Oregon, South Dakota, Vermont, and Virginia. Missouri, South Carolina, West Virginia, Wisconsin, and Washington, D.C. required UM only.
Triple-I cautions that requirements vary and that you should confirm with your state insurance department whether coverage is compulsory. In many other states, insurers must offer UM/UIM and you can decline it in writing. The Texas Department of Insurance, for example, says insurers must offer it and that to decline, you must tell the company in writing. Texas also notes that UM can pay in hit-and-run accidents, but only if you report the accident to police.
Laws change, so use our state auto insurance index and your state insurance department for the current rule.
Choosing limits
UM/UIM limits are often set to match your liability limits by default, but they are separate coverages. Consider:
- Your health coverage. If you have good health insurance, UM may fill gaps such as deductibles and lost income. Without it, UM may carry more weight.
- Your income. UM can compensate for lost wages in some states.
- Your state's rules. Some states require minimum UM limits. Others allow higher limits at extra cost.
- Stacking. A few states allow you to combine UM/UIM limits across multiple vehicles. This varies widely, so ask your insurer.
Our guide to how much liability car insurance you may need explains how limits work, and many of the same questions apply here.
How UM/UIM fits with other coverages
- Collision. Pays for your car damage regardless of fault, minus your deductible. UM property damage, where offered, may reduce or remove the deductible.
- Medical payments and PIP. Often pay medical bills first, regardless of fault. See medical payments coverage explained and personal injury protection explained.
- Health insurance. May pay first, and then seek reimbursement, depending on policy terms.
In a no-fault state, your own insurer pays certain injury costs regardless of fault, and UM/UIM still matters for costs beyond those limits. For background, read at-fault vs. no-fault states explained.
Hit-and-run accidents
If a driver flees, UM may apply, but insurers often require you to report the incident to police quickly, sometimes within a set number of hours or days, and to notify your insurer. Some policies require physical contact between vehicles for a hit-and-run claim. Read our guide to hit-and-run accidents and what insurance covers for details.
Steps if you are hit by an uninsured driver
- Get medical help. Call 911 if anyone is hurt.
- Collect information. Ask for the driver's name, plate number, and insurer. Photograph the scene.
- Report to police. A report is often needed for UM claims, especially in hit-and-run cases.
- Notify your insurer. Tell them the other driver may be uninsured and ask how UM applies.
- Keep records. Save bills, receipts, and notes about missed work.
For the full process, see what to do after a car accident.
Frequently asked questions
Is uninsured motorist coverage required?
In some states, yes. As of Triple-I's 2022 chart, about 19 jurisdictions required UM. In other states insurers must offer it and you can decline in writing. Check your state's current rule.
What is the difference between UM and UIM?
UM applies when the at-fault driver has no insurance, or is unidentified in a hit-and-run. UIM applies when the at-fault driver has insurance, but not enough to pay your losses.
Does UM cover damage to my car?
It depends on the state and policy. Some states offer UM property damage coverage. Otherwise your collision coverage pays for your car, minus your deductible.
Will a UM claim raise my rates?
Policies and state rules vary. Because you are not at fault in a typical UM claim, many states limit or prohibit surcharges, but ask your insurer and check your state's rules.
Does UM cover me in someone else's car or as a pedestrian?
Often yes, but policies differ. Read the definition of "insured" in your policy or ask your insurer.
Sources
- Insurance Information Institute – Background on: Compulsory auto/uninsured motorists
- NAIC – What Does Auto Insurance Cover?
- Texas Department of Insurance – Auto insurance guide
- Insurance Information Institute – Auto insurance basics: understanding your coverage
General information only. This guide explains general concepts and is not insurance, legal or financial advice. Rules and prices vary by state and insurer. Check your policy documents and speak to a licensed insurance professional or your state insurance department about your situation.